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Gem and rare-element pegmatites of Southern California.

The gem-bearing and rare-element-bearing pegmatites of Southern California have been the most prolific source of fine elbaite, morganite, kunzite, and other pegmatite minerals in North America since their discovery over 100 years ago. The province ranks among the major gem-producing and specimen-producing pegmatite regions in the world. Specimens from mines such as the Himalaya, Tourmaline Queen, Stewart, Pala Chief and Little Three mines are found in collections, both public and private, the world over.

INTRODUCTION

The pegmatite mines of Southern California are noted mainly for producing magnificent specimens of colored tourmaline, but other species have also contributed to the region's fame. The first recognized occurrence of lavender spodumene (given the varietal name kunzite) was from mines in the Pala district, and notable occurrences of pink beryl (morganite), blue-green beryl (aquamarine), topaz, spessartine, and many other pegmatite minerals are also found throughout the province.

Since the beginning of organized gem mining in Southern California near the end of the 19th century, production in the various districts has been sporadic, the intensity of exploitation depending largely on the economics of the gem and specimen market. Over the years, hundreds of mines and prospects have been established on pegmatites throughout the region. Despite the occasional spectacular find, only a few of these mines have ever proven to be economically viable.

The Southern California pegmatite province is located within the mountainous, semi-arid Peninsular Ranges of Southern California, and contains numerous individual pegmatite districts. The entire province extends from the San Jacinto Mountains in western Riverside County southward through San Diego County, into the northern portion of the Baja Peninsula of northwestern Mexico. Henley (1951) identified 14 separate pegmatite districts in Riverside and San Diego counties. The total number of individual pegmatites within these districts is in the thousands, if not tens of thousands. Jahns and Wright (1951) estimated that the Pala district alone contains more than 400 pegmatite dikes. Of these, only a small percentage have ever produced any gem or specimen material, and fewer still have ever produced material in any quantity. The focus of this article will be on those mines and districts that have historical significance or have produced major finds of gem or specimen material in recent years.

Compositionally, most of the Southern California pegmatites belong to the LCT (Lithium and Cesium enriched, and Tantalum> Niobium) category according to the classification proposed by Cerny (1991). Many are distinctly enriched in boron, as evidenced by the abundance of tourmaline. Alkali-enriched beryls (morganite and colorless goshenite varieties) are generally more common than aquamarine, and lithium enrichment is represented by the abundance of lepidolite, and to a lesser extent, spodumene in pegmatites throughout the region. The phosphorous content of the pegmatites appears highly variable. Some pegmatites, such as the Stewart, the Elizabeth R, and the Katerina in the Pala district and the Pack Rat in Jacumba, have an abundance of both primary and secondary phosphates, whereas others, such as the Himalaya mine in Mesa Grande, have very few phosphates. The occurrence of primary LiA1 silicates--principally spodumene--is likewise highly variable. Spodumene is abundant in many pegmatites in the Pala district , including the Pala Chief, Vandenberg, Katerina, and Stewart, but is rare or totally absent in pegmatites in the Mesa Grande and Ramona districts.

A few pegmatites show anomalous geochemical signatures. The Main Little Three dike in Ramona and some of the pegmatites on Aguanga Mountain are fluorine-enriched and are the only major sources of topaz in the region. The Hercules and several other dikes in the Ramona district are manganese-enriched, producing spessartine garnet and manganaxinite. A few of the pegmatites in Riverside County, most notably the Fano on Cahuilla Mountain, tend to produce aquamarine rather than morganite, and in the pocket zone schorl rather than elbaite.

PREVIOUS STUDIES

Numerous mineralogical and petrological studies have investigated the Southern California pegmatites over the past 100 years. Early investigations of the mineralogy and mining activities were done by U.S. Geological Survey mineralogist Waldemar T. Schaller and by George F Kunz, a gemologist with Tiffany and Company. Schaller's manuscript "The Tourmaline Field of Southern California" was, unfortunately, never completed, but Kunz's report "Gems, Jeweler's Materials, and Ornamental Stones of California" was published by the California Division of Mines in 1905 and remains the most important work available on the early history of gem mining in Southern California. More recently, Weber (1963) published a survey of mining activity in San Diego County, and Jahns (1979), Shigley et al. (1986), and Foord et at (1991) have published field trip guidebooks to several of the mining districts. Sinkankas (1959, 1976, 1997) gives much historical information on many of the major mines and districts in his three-volume series, Gemstones of North America. An autobiographical book by Rynerson (1967), a miner and lapidary who worked in many of the San Diego mines, gives an interesting personal narrative of his involvement in early mining and the gem cutting businesses in the region.

A number of important works have focused on individual districts or mines. Perhaps the most thoroughly studied is the Mesa Grande district. Jahns and Hanley (1953) produced an unpublished survey of the entire district, and Foord (1976) did a thorough examination of the mineralogy and petrology of the Himalaya dike system. Foord (1977) and Fisher et al. (1998) have published important studies of the Himalaya mine. A detailed study of the Pala district was published by Jahns and Wright (1951), and one of the Rincon district by Hanley (1951). Important articles on recent finds at the Little Three mine in the Ramona district have been published by Stern et al. (1986) and Foord et al. (1989). Less technical articles recounting various mining activities in the Southern California pegmatites include Carnahan (1960), Szenics (1970), Larson (1972, 1977), Marcusson (1985), Gefner and Fisher (1997), and Fisher (1999).

In addition, the Southern California pegmatites have served as a model for the understanding of how complex granitic pegmatites form. Field investigations involving these pegmatites, particularly in the Pala district, have formed the basis for a number of important studies including Jahns and Tuttle (1963), Jahns and Burnham (1969), and Webber et at (1997).

LOCATION and GEOLOGICAL SETTING

Most of the gem-bearing pegmatites of Southern California have been intruded into rocks of the Cretaceous-age Peninsular Ranges Batholith--formerly referred ton the Southern California Batholith. These granitic rocks form the core of the Peninsular Ranges, which extend from Riverside County to the southern tip of the Baja Peninsula (Foord et at, 1991). The batholith consists of numerous individual plutons ranging in size from <10 to 40 km across; it has been divided by Todd and Shaw (1985) into two sections based on chemical, physical, and lithologic differences. A younger, more felsic, late post-tectonic zone lies to the east, while an older, more mafic, syntectonic zone lies to the west.

Potassium-argon cooling dates for biotite and hornblende have given ages ranging between 143 and 101 Ma (million years) for the rocks of the Peninsular Ranges Batholith (Krnmmenacher et al., 1975). Foord (1976) reported two K/Ar ages from micas associated with the Himalaya dike in the Mesa Grande district. Muscovite from a pocket in the San Diego mine yielded an apparent age of 98.4 [+ or -] 4 Ma, while biotite which had formed at the time of dike emplacement in the host norite yielded a similar age of 97.1 [+ or -] 4 Ma. More recently, Snee and Foord (1991) have reported [[blank.sup.40][Ar/.sup.39] Ar dates of 95.4 [+ or -] 0.3 Ma for muscovite and a range of 93.1 [+ or -] 0.3 Ma to 93.4 [+ or -] 0.3 Ma for compositionally zoned lepidolite from the Himalaya mine.

The emplacement of pegmatites within the Peninsular Ranges appears to have been strongly controlled by the lithology of the host rock. While a few pegmatites--notably those in the Jacumba district and around Cahuilla Mountain in Riverside County (Geffner and Fisher, 1997)--are hosted by pre-batholithic schists, the majority have been intruded into the San Marcos Gabbro, a mafic unit in the western subsection of the batholith. [[blank.sup.40][Ar/.sup.39] Ar dates from hornblende and biotite from the San Marcos Gabbro adjacent to the Himalaya dike system in Mesa Grande were reset to 100 Ma by the emplacement of the pegmatites (Snee and Foord, 1991).

HISTORY

The first reported find of gem tourmaline in California occurred at the site of the Columbia mine on Thomas Mountain in central Riverside County in 1872 (Kunz, 1905a). The discovery is credited to a local prospector, Mr. Henry Hamilton. This find apparently received little publicity, perhaps because of secrecy on the part of the miners. The next report of colored tourmaline in California was in 1892, when pink elbaite was discovered embedded in massive lepidolite at the Stewart mine, in Pala. The mine was being worked at the time for lepidolite as a source of lithium and, as the tourmaline discovered was not of gem quality, it again attracted only minor attention among mineral collectors of the time.

The first major find of gem material in Southern California occurred in 1898 at the Himalaya mine in Mesa Grande. American Indians probably knew about these deposits for some time prior to this, however, as elbaite crystals have been discovered in Indian graves in the area (Kunz, 1905b). The Himalaya pegmatite immediately began producing large quantities of pink and green elbaite and, when word got out about the discovery, a flurry of prospecting activity began throughout the region. As a result, within the next several years most of the important gem-producing pegmatites in the region had been discovered. Numerous mining claims were established in the Pala, Rincon, Aguanga Mountain, and Cahuilla Mountain districts in 1902 and further south at Ramona and Jacumba during the following year.

During the first decade of the 20th century, Imperial China was a major consumer of California elbaite; the Dowager Empress, Tz'u Hsi, was especially fond of the pink and red varieties (Bancroft, 1995). The Chinese demand was principally for carving-grade material rather than facet-grade elbaite, and China was therefore an important market for material that was not of sufficiently high gem grade to be salable in the United States. Only pink elbaite was desirable to the Chinese; multi-colored crystals were usually broken up and the unwanted blue or green portions discarded. Rumors still circulate about large hoards of unsalable gem-green elbaite supposedly buried on certain mining properties or forgotten in New York warehouses. As a result of this practice, relatively few specimens of elbaite from this early period of mining survive today. However, Chinese artifacts from this period, such as snuff bottles carved from California elbaite, can still occasionally be found on the antiques market.

The other important gemstones produced by the Southern California mines during this period were kunzite and morganite. Prior to its discovery in the pegmatites of Hiriart Mountain in the Pala district during late 1902, the lilac-colored variety of gem spodumene was unknown. The gem was quickly popularized by George Kunz, a gemologist with Tiffany and Company, who is credited with first identifying it (there is some dispute over this, however; see Sinkankas, 1976). Morganite, while previously known as "rose beryl" from a few locations such as Madagascar and Brazil, had not been found anywhere before in abundance. The name "morganite" was given to this pink variety of beryl by Kunz in 1910, in honor of American banker and mineral collector J. P. Morgan, who also happened to be one of Kunz's best customers (see Conklin, 1988).

When the Imperial Chinese aristocracy was overthrown by Sun Yat-Sen in the Revolution of 1911-1912 [Note--this was not the same as the Boxer Rebellion of 1900-1903], the demand for California gemstones in China quickly dried up. The loss of this market, combined with a domestic oversupply of gemstones, resulted in a collapse of the local gem market and by 1913 most gem mining operations in Southern California had ceased because of bankruptcy. Gem prices remained depressed for several decades thereafter; between 1913 and the early 1950's mining activities throughout Southern California were small-scale and sporadic.

By the early 1950's gem prices had begun to rise. This, along with an increasing interest in mineral collecting, led to renewed attempts at organized mining, particularly in the Pala, Mesa Grande, and Ramona districts, and such efforts have continued through to the present day. Mines which have been successfully reopened include the Stewart, Tourmaline Queen, White Queen, Vandenberg, Elizabeth R, Pala Chief and Katerina in the Pala District, the Himalaya in Mesa Grande, and the Little Three and Hercules in Ramona. In addition, a number of new mines have produced gem and specimen material, particularly in Riverside County and Northern Baja California. Although the more recent mining activities have not produced the same volume of gem and specimen material as was recovered at the beginning of the 20th century, many spectacular finds of elbaite, kunzite, morganite, spessartine, and topaz have been made.

MAJOR PEGMATITE DISTRICTS

Riverside County

The pegmatite districts of Riverside County, which make up the northern limits of the Southern California pegmatite province, are not as well defined as those farther south in San Diego County, and little has been recorded about their mineralogy and history. Much of the area is still remote and sparsely populated, and the exact location of many older mines and prospects is today far from certain. To further complicate matters, some mining claims have been renamed by new owner , making it difficult to know if published descriptions are referring to the same or different properties.

Fano Mine

Perhaps the best-known pegmatite mine in Riverside County is the Fano (or Fano-Simmons) mine. Originally claimed by Bert Simmons in 1902, the Fano mine is a patented claim consisting mostly of surface excavations on a pegmatite dike that lies on top of a ridge located on the north flanks of Cahuilla Mountain (also spelled Coahuila) near the town of Anza. Kunz (1905a) reports that the pegmatite initially produced kunzite, colored tourmaline, and lepidolite. Little evidence of lithium-bearing minerals is seen in current exposures of the pegmatite, and the mine is now better known for its somewhat limited production of well-crystallized aquamarine and schorl in recent years. Commercial attempts to work the mine appear to have be n limited to the first decade of the 20th century; the mine has since been operated, for the most part, by hobbyists and highgraders. Digging by the latter has, in recent years, produced a series of debris-filled pits that now obscure much of the pegmatite.

Schindler Mine

Located near the Fano is the Schindler mine. According to Tucker and Sampson (1945) this mine produced pink and green tourmaline, beryl of unspecified color, columbite, and quartz crystals sometime prior to World War II. The mine does not appear to have been worked in recent years and its present status is unknown.

Lithia Dike

Two more recently discovered pegmatites have produced limited amounts of gem and specimen material during the last few decades. The Lithia Dike, an unpatented claim located on the southeast flank of Cahuilla Mountain, encompasses at least two separate pegmatite dikes, intruded into the Paleozoic schists which blanket the mountain. The property was originally discovered by local miner Phil Osborne in the early 1970's. Osborne, along with partners Bill Magee and Ed Link, periodically worked the lower of the two dikes on the claim for around ten years. During this time they found several pockets containing pink, green, and bicolored elbaite. One pocket uncovered by Magee in late 1983 yielded a number of well-formed specimens of green elbaite and morganite, associated with cleavelandite, microcline and smoky quartz. Several specimens from this find are now in the collection of the Los Angeles County Museum of Natural History. Another pocket uncovered at about this time produced around 75 gemmy, bicolored elbaite crystals which, according to witnesses, may have been some of the finest ever found in the region (C. Graeber, personal communication, 1994). Unfortunately, most were used for lapidary purposes, and consequently few specimens from this period of mining survive.

The claim was purchased from Osborne by Paul Geffner in 1989. In 1996, after resolving problems with access rights to the property, he and several partners began several months of full-time mining. Work focused on the relatively untouched upper dike, and a deep trench was excavated into the hillside, following the dike down dip. A number of pockets were encountered, producing some excellent pink, green, and bicolored elbaite crystals and gem rough, along with some schorl, morganite, kunzite, and small etched gemmy fragments of spessartine. The overall amount of material found, however, was not enough to justify the cost of a mechanized mining operation, and the property has been idle since. For a more detailed description of this mining venture, see Geffner and Fisher (1997).

Audrey Lynn Mine

The Audrey Lynn, an unpatented claim, is located on the northwest flank of Cahuilla Mountain near Juan Diego Flats. The deposit was discovered by Phil Osborne and worked by him for several years in the late 1980's and early 1990's. This prospect produced a limited number of well-formed aquamarine crystals (both on feldspar matrix and as single crystals), lustrous and often large schorl crystals, and smoky quartz. Specimens of spessartine, cassiterite and columbite-group minerals were also recovered. This deposit appears to be exhausted and no further work has been done for a number of years.

Columbia Mine

To the east of Cahuilla Mountain lies Thomas Mountain, the site of the first reported find of gem tourmaline in California. Located on the southeast ridge of Thomas Mountain is the historically important Columbia mine (also known as the Belo Horizonte). According to Kunz (1905a) the Columbia produced some large green and pink tourmaline crystals of excellent color around the turn of the century, but more recent attempts to work the mine have had only limited success (Sinkankas, 1959). The mine consists of a series of four claims, which are currently owned by Matt Taylor, a geology student who works it on a part-time basis, mostly as a research project. The main elbaite-bearing pegmatite is unusual in that it contains almost no mica of any kind (Taylor and Foord, 1993).

Jensen Quarry

Perhaps the northern-most reported occurrence of a gem-bearing pegmatite in Southern California is in the Jensen quarry, just west of the city of Riverside. In the early 1980's a dike known as the J27 pegmatite, exposed in the quarry wall, was excavated by a group of mineral collectors. A number of good specimens of bicolored elbaite and schorl were recovered, along with a number of other rare and interesting minerals including clinobisvanite, stibiotantalite, danburite, hambergite, pyrochlore, and synchysite (DeVito and Ordway, 1984).

Chihuahua Valley

Blue Lady Mine

The Chihuahua Valley district is located in a sparsely inhabited area of north-central San Diego County, just south of the Riverside County border. The district contains numerous pegmatite dikes, none of which have ever been successfully worked on a commercial basis. The most important mine in this district is the unpatented Blue Lady claim (also known at various times as the Blue Bell, Blue Tourmaline, or Pearson mine).

The Blue Lady pegmatite was discovered in 1905 by Bert Simmons, who briefly worked it for gem tourmaline. A few years later the pegmatite was prospected for cassiterite as a source of tin, but has since been worked solely by mineral collectors. The workings at the Blue Lady mine currently consist of a number of pits and open cuts, along with one short tunnel on the dike, which is exposed along the north side of the valley.

The mine is known largely for its output of well-formed pencil-like crystals of dark blue tourmaline (schorl-elbaite?), which occur abundantly in the dike, often associated with quartz and feldspar. However these tourmaline crystals are rarely, if ever of gem quality. The mine also occasionally produces specimens of both aquamarine and morganite beryl, spessartine, topaz, apatite, and large, well-formed crystals of perthitic microdine. A number of excellent specimens, including a particularly large and well-formed crystal of peach-colored morganite associated with smoky quartz from the mine are in the collection of the Los Angeles County Museum of Natural History.

Blue Chihuahua Mine

The Blue Chihuahua claim is located a little to the east of the Blue Lady, on the same side of the valley. During the late 1960's a group of collectors including Josie Scripps and Bryant Harris worked this pegmatite, recovering some very good herderite and microcline specimens, along with some topaz, schorl, and cassiterite. The pegmatite was largely removed during the mining operation and little, if anything, has come from this claim since.

Aguanga Mountain District

About 10 kilometers southwest of Chihuahua Valley, near the town of Oak Grove lies Aguanga Mountain, which is actually a ridge running southeast from Palomar Mountain, site of the famous astronomical observatory. Two mines in this district, the Maple Lode and the Ware (also known as the Emeralite no. 2, Mountain Lily, or Gem Mine no. 1) have produced specimens of note.

Ware Mine

The patented Ware mine is located on the northeast side of the ridge, near its crest, and exploits a pegmatite that dips gently to the southwest, into the hillside. The current workings consist of an open cut of approximately 100 meters along the pegmatite, and at least two tunnels, one of which has completely collapsed. The extent of the underground workings is unknown. The mine was originally discovered in 1903 by Bert Simmons and named the Gem Mine no. 1 (Weber, 1963). According to Kunz (1905a) the mine produced a modest amount of tourmaline "... nodules of beautiful coloring, deep blues, reds, and an almost emerald green predominating."

The mine is currently named after its most famous owner, John W. Ware, a San Diego jeweler who operated the mine during the 1920's and 30's. During this period, Ware worked the mine primarily for pale blue topaz, which he marketed through his jewelry shop. More recent attempts to work the mine have seen only limited success. During the early 1980's the mine was worked briefly by local collectors Bill Magee and Ed Link. Little material appears to have been found, but one gemmy pale blue topaz crystal recovered by Magee is now in the collection of the Los Angeles County Museum of Natural History.

Maple Lode Mine

Directly south of the Ware mine, on the opposite side of the ridge, is the Maple Lode mine. This mine is an unpatented claim consisting of two bench cuts along the pegmatite and at least two largely collapsed tunnels following the dike northward into the hillside. The pegmatite dike is highly fractured and broken up, possibly as a result of slumping of the hillside where the dike is exposed. From the geometry of the ridge, it appears that the Ware and Maple Lode mines may actually work the same dike from opposite sides of the ridge.

Weber (1963) states that the Maple Lode was probably first worked around 1903, at the same time as the Ware, but specific references to the mine in early literature cannot be found. The mine is currently owned by local miner Roland Reed who, along with several partners, worked the mine during the late 1970's and early 1980's. Reed and his partners recovered a number of well-formed topaz crystals ranging in color from medium blue to colorless to pale green, along with numerous blue and bicolored blue-pink elbaite crystals. The tourmalines usually occur as small "pencils" up to around 5 cm long and are sometimes a bright sky-blue in color. Some very good red., tabular apatite crystals, up to 7.5 cm in size, were recovered as well. Matrix specimens are very rare from the Maple Lode because of the brecciated nature of the dike, and the crystal-bearing pockets are reported to be often no more than sand-filled and clay-filled cavities between blocks of pegmatite (Fisher, 1995).

Warner Springs District

The Warner Springs district is an area of scattered pegmatites located just south of Aguanga Mountain, near the town of Warner Springs. The pegmatites of this area, like most others in the region, were originally prospected during the first decade of the 20th century, but little information remains as to what, if anything, may have been found.

Cryo-Genie Mine

The best known pegmatite prospect in this area is the Cryo-Genie--originally known as the Lost Valley Truck Trail Claim, which is located approximately 2 miles north-northwest of Warner Springs. Weber (1963) reports that several shallow cuts and trenches were dug along the dike during the 1910's or 1920's but gives no further details. The claim was re-established in 1962 by the San Diego Gem and Mineral Society (J. Clanin, personal communication, 2001). Ownership of the claim was then picked up by mineral collector Bart Cannon in 1973, who gave the property its current name. Cannon sold the claim to the current owners, Ken and Dana Gochenour in the mid 1980's.

During most of its existence, the claim has been little more than a hobby mine, producing the occasional crystal of schorl or dark blue to green elbaite. In the spring of 2001 the Gochenours enlisted the help of Jim Clanin and John Klinke, a couple of experienced geologists and miners, and began an organized mining project on the dike. Tunneling down-dip on the dike, the crew quickly encountered several pockets containing quartz, feldspars, and fine "jack-straw" like groups of pale green and pink elbaite. After several months work a major tourmaline-bearing pocket was found. Elbaite crystals from the pocket are mostly a medium pastel-pink color, and most are deeply striated with pedion terminations. In all, seven major specimens were recovered (K. Gochenour, personal communication, 2001), the largest being a tapering, 19-cm, doubly terminated crystal with a bluish green cap at the pyramidal termination. Another interesting specimen recovered from the pocket consisted of two slightly divergent pink pencil-like elbaite crystals, approximately 5 cm long, growing from a base of ferrocolumbite. Along with the elbaite, several gemmy crystals of beryl (both aquamarine and morganite color varieties) were found.

Pala District

The Pala district, located in northwestern San Diego County near the village of Pala, is perhaps the most famous of all the pegmatite districts in Southern California. The district encompasses four hills: Queen Mountain (formerly called Pala Mountain) to the west, Chief Mountain and Little Chief Mountain in the middle, and Hiriart Mountain to the east. These hills are host to hundreds of individual pegmatite dikes.

The pegmatites of the Pala district are usually tabular to sheet-like in shape. The average thickness is around 3 meters, though there is considerable variation, and most are at least 120 meters long. The dikes are largely parallel, striking northward and dipping toward the west at an average of 20[degrees] (Jahns and Wright, 1951).

Over the years, numerous mines and prospects have been established on pegmatites in the district; Jahns and Wright (1951) list 74, but only a small number of these have ever produced gem or specimen material in any quantity. The few that have, however, have been the source of some of the finest specimens of elbaite, kunzite, and morganite known. The most productive dikes are located on Queen, Chief, and Hiriart Mountains. Little Chief Mountain is host to numerous pegmatites, but none is reported to have ever produced much specimen or gem materials.

Most of the mines in the Pala district are located within the boundaries of the Pala Indian Reservation. The reservation was not formally established until after most of the mining claims in the district had been filed, but in recent years many of these claims have become inactive and have fallen under tribal control. A few of the more famous and productive mines still remain as valid claims, but it is unlikely that many of the others will be worked again in the foreseeable future.

Stewart Mine

The first reported mining in the Pala district was at the Stewart (or Stewart Lithia) mine, a patented claim located low on the southern slope of Queen Mountain. The Stewart dike is a very large pegmatite, in places exceeding 30 meters in thickness. In the southern portion of the dike the core zone is made up of large masses of fine-grained purple lepidolite containing numerous embedded needle-like crystals of pink elbaite. The tourmaline is highly fractured and not of gem quality, but the combination with lepidolite makes attractive specimens for which the mine is well known.

Kunz (1905b) reported that the Stewart was first claimed as a mercury mine by a prospector who mistakenly thought the pink tourmaline to be cinnabar. The deposit was re-claimed as a source of building stone by another individual who thought the massive lepidolite to be a peculiar type of marble. In the 1890's the lepidolite was finally recognized for what it is, and the mine soon became the largest source of lithium known at the time in North America. The mine was worked off and on until 1928 for lepidolite (Weber, 1963), but the gem-producing potential of the pegmatite was not fully recognized at the time because gem-grade elbaite is not found in the same portions of the dike as the massive deposits of lepidolite.

In 1968 the mine was purchased (along with the Tourmaline Queen and Pala Chief) by Ed Swoboda, a Los Angeles jeweler and mineral collector. Swoboda, along with partner Bill Larson, established Pala Properties International (PPI) to work these mines and market gem rough and mineral specimens. Work began immediately at the Stewart and by late the next year elbaite-bearing pockets had been uncovered (Szenics, 1970). The mine was successfully operated by PPI between 1969 and 1972, producing a fair amount of elbaite, along with minor amounts of morganite and kunzite.

The Stewart was worked only occasionally after operations at the nearby Tourmaline Queen mine became successful in 1972, and after the break-up of the Larson-Swoboda partnership in the late 1970's, the mine was purchased by a syndicate of owners based in Germany. This syndicate, relying on hired local management, operated the mine through the 1980's with limited success. Because of the absentee ownership, oversight of the mine was rather lax during this period and much unauthorized work (or "high-grading") is reported to have occurred.

In 1990, operation of the mine was taken over by Millennium, Inc., headed by Blue Sheppard. Sheppard was successful in increasing security at the mine, and continues to operate it on a small scale today. Faceted elbaite, gem rough, and mineral specimens from the mine are marketed through his retail store, Gems of Pala, located just outside the village of Pala.

Elbaite from the Stewart mine is predominantly pink, and the vivid "hot" pink varieties are among the most brilliantly colored tourmaline found in Southern California. The mine has produced elbaite in a wide variety of other colors, however, including blue, green, and various color combinations. Most elbaite from the Stewart mine is of lapidary rather than specimen grade; intact undamaged tourmaline crystals, much less good matrix specimens, are relatively rare. The core zone of the pegmatite appears to have been broken up by natural forces at some point after formation and the contents of most pockets were shattered. When they do occur, matrix specimens from the Stewart mine are distinctive because any associated lepidolite is usually much finer grained than that from other mines in the district.

Minor amounts of morganite, spodumene, and mangano-columbite-manganotantalite (Shigley et al., 1986) have been found as well. Morganite crystals are usually a very pale pink and typically have a tabular habit, showing development of pinacoid and pyramid faces. Spodumene is found in some pockets as small, etched fragments of what had originally been larger crystals. Colors found include pink, lilac, blue, yellow, and colorless, but crystals are usually small and pale in comparison to spodumene from other mines in the district.

The Stewart pegmatite is also very rich in both primary and secondary phosphate minerals. Lithiophilite is the principal primary phosphate mineral (Shigley and Brown, 1985), but amblygonite, triplite, and triphylite (possibly misidentified lithiophilite, A. R. Kampf, personal communication, 2000) have also been reported (Jahns and Wright, 1951). Lithiophilite occurs as sooty black, well formed, equant crystals as well as irregular masses, sometimes in excess of 10 cm in size. The lithiophilite is almost always at least partially altered to secondary phosphates, and oxides of manganese and iron. Secondary phosphates found in the Stewart pegmatite include hureaulite, sicklerite, purpurite, heterosite, stewartite, and phosphosiderite. Apatite appears to be rare.

Tourmaline Queen Mine

Located on the northeast slope near the summit of Queen Mountain, the patented Tourmaline Queen mine is one of the most well-known elbaite-producing pegmatites in California, if not the world. Specimens of bicolored elbaite from the famous "blue cap" find of 1972 (see the accompanying article by Ed Swoboda) are considered some of the finest in the world. Despite this renown, no detailed studies of the mine's mineralogy and geology have ever been conducted and little information on the mine has ever been published.

Kunz (1905b) reports that the Tourmaline Queen mine was established as a quartz claim in 1903 by Frank Salmons and several associates, but at the time of Kunz's report, little mining had yet been done. Soon thereafter, the mine began producing and until 1912 was, along with the Himalaya mine in the Mesa Grande district, one of the leading sources of colored tourmaline in Southern California. After the collapse of the gem market, the mine was idle for some time. Sinkankas (1959) reports that some small-scale mining was done during the 1940's and 1950's, but gives few details.

Pala Properties International began full time work at the mine during the summer of 1971, shifting their operation from the Stewart mine, further down the hill. Under the direction of John McLean, tunneling began in September, and several small pockets were encountered through the fall. The famous "Blue Cap" pocket was first encountered on December 31, 1971, and excavation of this pocket (actually a series of interconnected pockets) continued through the next month (Larson, 1972). Elbaite crystals from this pocket are a rich reddish-pink color with a deep blue band at the termination. Many crystals are quite large, some exceeding 20 cm in length, giving rise to the informal unit of measurement for tourmaline crystals known as the "beer can". A number of sizable specimens were recovered associated with quartz and cleavelandite, and a few with well-formed, pale crystals of morganite. In all, around 33 major tourmaline specimens were produced from this pocket (W. Larson, personal communication, 1999) along with a few smaller ones. Specimens from this pocket can be seen in many major museum collections in both Europe and the North America, and some, such as "The Candelabra" now in the National Museum of Natural History (Smithsonian Institution) and the "Rabbit Ears" in the Houston Museum of Natural Science, are among the best known tourmaline specimens ever found.

Pala Properties International continued work at the Queen mine through 1975, finding at least 10 significant pockets in all (Sinkankas, 1976). The mine was finally closed after being actively worked for the better part of the last year without finding any new pockets. Since then, several attempts have been made to work the mine with little success. For several years during the early to mid-1990's, Roland Reed leased and worked the mine along with several partners. No significant finds were made, however, and the mine (as of this writing) is once again being operated by long-time owner Ed Swoboda.

Typical elbaite crystals from the Tourmaline Queen mine are heavily striated trigonal prisms with simple pedion terminations, which may be either glassy or matte. Smaller parallel growth or "side car" crystals are commonly associated with larger tourmalines and, as previously mentioned, individual crystals can be quite large. Various shades of blue and pink are the most common colors. Pocket crystals will often have a core of pink, ranging from pale to a rich reddish color, with a thin blue layer on the prism and pedion faces. The blue may range from a pale bluish gray to a deep indigo-blue dark enough to mask the interior color of the crystal. Some pockets have produced elbaite that is mostly blue, with little or no pink. Green elbaite appears to be relatively rare in this pegmatite. When crystals do occur, they often have a dull grayish cast.

Pink beryl or "morganite" also occurs in pockets in the Tourmaline Queen mine, sometimes directly associated with elbaite. Typically, morganite forms tabular crystals with prominent pinacoid faces that are usually glassy. Prism and pyramid faces are usually present and often have a dull or matte surface. The color is usually pale pink, and smaller crystals may appear to be almost colorless. Morganite crystals from the Tourmaline Queen mine are often quite similar in appearance to those from the Stewart mine. Distinguishing characteristics include associated lepidolite, which will generally be much coarser grained on specimens from the Tourmaline Queen mine than on those from the Stewart, and elbaite, which may be bi-colored from the Tourmaline Queen mine, but is usually pink from the Stewart.

Quartz, albite (var. cleavelandite), microcline, and lepidolite are common in pockets, while spodumene has not been reported from the Tourmaline Queen. Quartz crystals are often large and well-formed, and range from colorless to pale smoky, sometimes with a yellow cast. As the Tourmaline Queen pegmatite has never received a detailed mineralogical study, many of the rare minerals of the pegmatite have never been documented. Small crystals of uraniumbearing microlite can occasionally be found embedded in elbaite crystals and are distinguished by the radiation damage halos they create. Spessartine, apatite, stilbite and minerals of the columbite tantalite group have also been found in small amounts.

Tourmaline King Mine

The patented Tourmaline King mine is located high on Queen Mountain, to the north of the summit. The mine was originally claimed in 1903 by a Mr. Schuyler and is reported to have produced much gem tourmaline of exceptional quality during the early years of its operation. Very little has been found since, despite several attempts to reopen the mine, and it is considered possible that most of the early production came from a single large pocket (Jahns and Wright, 1951). The occurrence of other gem or rare-element minerals from the mine has not been documented.

Elbaite crystals from the Tourmaline King mine are often similar in appearance to those from the nearby Tourmaline Queen mine. Large pink and bicolored pink-blue and pink-green crystals are common. Crystals usually occur as moderately to heavily striated trigonal prisms with simple pedion terminations. Without documentation, it is difficult, if not impossible, to tell older specimens from the King and Queen mines apart. Greens appear to have been more common from the King mine, however. The best specimen known to have come from the King mine is "The Steamboat," a 27 x 32-cm specimen consisting of two parallel, bicolored elbaite crystals on quartz and cleavelandite. This specimen was originally in the Roebling collection and is now in the National Museum of Natural History (Smithsonian Institution) (see Bancroft, 1973).

Katerina and Vandenberg Mines

Hiriart Mountain is located on the eastern side of the Pala district and is host to a complex system of inter-connected, mineralogically similar pegmatites that are exposed on the southern, eastern, and northern flanks of the mountain. Numerous mines and prospects have been developed on Hiriart Mountain since the beginning of the 20th century, but in recent years the White Queen, San Pedro, Vandenberg, and Katerina have been the most important producers of gem and specimen material. Other mines on Hiriart Mountain that have produced gem or specimen materials in the past include the Senpe, Anita, Fargo, El Molino, and Naylor mines. All the mining claims on Hiriart Mountain are unpatented.

Spodumene (including kunzite) and beryl (mostly morganite) are the principle gem minerals found in most mines on Hiriart Mountain, and it was in these pegmatites that kunzite, the lilac-colored gem variety of spodumene, was first discovered (Schaller, 1903; Kunz, 1904). Many of these pegmatites are also enriched in phosphate and bismuth-containing minerals, as well as minerals of the columbite group, which usually occur in or around the quartz core zones of the dikes. Phosphate minerals include primary lithiophilite, triphylite, and amblygonite, and numerous alteration products including hureaulite, purpurite, and sicklerite. Bismuthcontaining minerals found include native bismuth, bismite, bismutite, bismuthinite, and beyerite (Jahns and Wright, 1951). Pucherite and clinobisvanite have also been reported (Foord et al., 1991).

Unlike in the pegmatites further west in the district, tourmaline is relatively scarce in the core and pocket zones of dikes on Hiriart Mountain. When they do occur, tourmaline crystals from the Hiriart Mountain pegmatites are usually small and dark indigo-blue in color, and though often quite flawless, are usually too dark to cut as gemstones.

The Katerina and Vandenberg mines, along with most of the others on Hiriart Mountain, were originally discovered by the father and son team of Marion and Fred Sickler, along with French Basque prospectors Bernardo Hiriart and Pedro Peiletch during 1902 and 1903. During the following decade, the Katerina and Vandenberg, along with the neighboring Pala Chief mine, were the only major sources known for gem kunzite (Kunz, 1905b). The Sicklers are reported to have originally found colorless fragments of spodumene on the site of the White Queen mine around 1900, but were unable to identify the mineral. This material was found again when they began working the Katerina, and some specimens were ultimately sent to George Kunz, a gemologist with Tiffany and Company in New York, for identification. It was this material that Kunz identified as the lilac-colored gem variety of spodumene and that was later named in his honor (Sinkankas, 1959).

Between 1903 and 1912 the Sicklers, Hiriart, and Peilitch worked the Vandenberg, Katerina, and several other nearby mines and are reported to have produced a fair amount of kunzite and beryl (Sinkankas, 1959). Full-time mining came to a halt in 1912 with the collapse of the tourmaline market. Most work since that time was done by "unofficial" visitors until several of the mines, including the Vandenberg, Katerina, and White Queen properties, were purchased by George Ashley in 1948. During the 1950's, Ashley successfully worked both the Katerina and the nearby Vandenberg mine for kunzite and is said to have found one pocket in particular which produced enough gem material to support his rather modest lifestyle for many years. One often-repeated story has it that Ashley purchased the mines from Fred Sickler with funds generated through the sale of kunzite he had "unofficially" collected there prior to the purchase.

Ashley sold both mines in the late 1950's and only occasional mining has been accomplished at either mine since. The Vandenberg was purchased and briefly worked in the early 1970's by Norm Dawson, who produced around 12 kg of high-quality kunzite, along with some morganite and large smoky quartz crystals (Sinkankas, 1976). The mining claim on the Vandenberg property was recently ruled invalid by the Bureau of Land Management (BLM) and possession of the mine has now reverted to the Pain Indian tribe.

Serious attempts to work the Katerina began again when the current operators, Otto Komarek and Byron Weege, became partners in the mine during the late 1980's. Komarek and Weege began work on the property in 1990, quickly finding pockets containing numerous large "cathedral" habit quartz crystals, many colored blue by the inclusion of micro-tourmaline needles, as well as some pale pink morganite specimens. A subsequent dispute with the Pala Indian tribe over the validity of the mining claim forced a halt to mining for several years while the status of the claim was under review by the BLM. During this process Komarek and Weege were allowed to resume mining for a short time in order to make a "discovery" which would establish the mine's economic viability. They found a pocket containing numerous morganite specimens, most on a matrix of cleavelandite and quartz, along with a modest amount of kunzite. In late 1997, the BLM ruled in favor of the mine owners and work on the claim has recently resumed. In November of 1998, a small find of kunzite was made in the area of the dike worked by Ashley during the 1950's (Fisher, 1999).

White Queen Mine

The White Queen mine is located uphill from the Katerina mine, just below the summit on the south side of Hiriart Mountain. Although the White Queen was the site of the original discovery of kunzite by Fred Sickler around 1900 (see Conklin, 1988), very little mining took place on the property until the late 1950's. The mine was among the properties purchased from Sickler by George Ashley in 1947, but he sold it the next year to Norm Dawson without having done any work there. Dawson did not begin work at the mine until 1959. After tunneling for approximately 25 feet (7.5 meters) along the pegmatite he encountered a pocket that, once excavated, was large enough that "... a grown man could stand within it and observe numerous quartz crystals of large size descending from the ceiling" (Sinkankas, 1976). This pocket produced numerous fine specimens of morganite and much gem rough, along with many large, seemingly opaque quartz crystals. When sawn length-wise and polished, these quartz crystals revealed very intric ate and attractive inclusions of pink and tan montmorillionite clay. Sinkankas (1976) states that this pocket produced an estimated 5600 kg of quartz crystals and 80-120 kg of morganite. Other minerals found included dark blue fibrous tourmaline, columbite-tantalite group minerals, phosphates including apatite crystals and massive lithiophilite and amblygonite, and very attractive clusters of albite (var. cleavelandite). Several smaller pockets of similar composition were found during the mid- to late 1960's. In 1973 another large pocket was found which yielded approximately 6000 kg of quartz crystals and 30 kg of morgaaite.

Little subsequent work was done at the White Queen until 1990 when Dawson's sons Bob and Ken, along with several other partners, began a new tunnel on the pegmatite. In early September of that year, they encountered a pocket measuring approximately 2.5 meters across, which produced nearly 200 well-formed specimens of morganite. Most crystals are highly lustrous and up to 8 cm in size; many are on a cleavelandite matrix (Foord et al., 1991). Specimens from this pocket are widely regarded as being among the finest ever produced by the mine. When first removed from the mine, most morganite crystals were a peach to salmon-pink color. However, this color changes rapidly to a pure pink on exposure to direct sunlight, and many specimens have since undergone this color change.

Shortly after this find, a dispute arose with the Pala Indian tribe over the validity of the mining claim. The BLM subsequently ruled the claim invalid and ownership has reverted to the tribe. Several parties have recently attempted to lease the claim from the tribe, but to date no agreements have been reached.

Foitite is a recently described member of the tourmaline group (MacDonald et al., 1993), the type specimens of which were found in and old collection, labeled only as having come from "Southern California," so the actual type locality is currently unknown; however, foitite has since been identified from material collected at the White Queen mine. The foitite from the White Queen is similar in appearance to much of the tourmaline found in other nearby mines, but no studies have yet been published on how widespread foitite might be in the pegmatites of Hiriart Mountain.

San Pedro Mine

The San Pedro mine is located on the northern flank of Hiriart Mountain and, along with the nearby Anita and Senpe mines, comprises the northernmost of the group of claims originally discovered by the Sicklers around 1903. Kunz (1905b) reports that some kunzite, beryl, and tourmaline were produced from the San Pedro claim at the time, but gives no further details. The San Pedro, Anita, and Senpe (along with the other claims of the Sickler group) were purchased from Fred Sickler by George Ashley I 1947. Ashley appears not to have done any work on these claims, and sold them almost immediately to Charlie Reynolds. Reynolds began work on the San Pedro and in 1951 encountered a large pocket which produced approximately 300 pounds of spodumene of various colors, including pink, colorless, and pale green (Sinkankas, 1957). Reynolds continued to work the mine through the 1950's with varying degrees of success. The claim was sold in the early 1960's and little appears to have been done there since. The San Pedro, Sen pe and Anita claims were recently ruled invalid by the Bureau of Land Management (BLM) and have now reverted to the Pala Indian tribe.

Pala Chief Mine

The Pala Chief mine is a patented claim that works a complex, braided system of pegmatite dikes located on the northwest side of Chief Mountain, in the center of the Pala district. The mine was opened in 1903 by Frank Salmons, John Gibbons, Bernardo Hiriart, and Pedro Peiletch, and was for the next ten years the world's foremost source of gem spodumene. While the lilaccolored gem variety of spodumene now known as kunzite was first discovered in the pegmatites of neighboring Hiriart Mountain, the Pala Chief mine surpassed all others with respect to the quality and quantity of kunzite it produced. Kuozite crystals from the Pala Chief mine tended to be, on average, larger and of better color than those found elsewhere in Southern California. Stones cut from Pala Chief kunzite found a ready market through Tiffany and Company of New York. Kunzite crystals from the Pala Chief mine are almost always twinned on (100) and can be distinguished from those from the mines on Hiriart Mountain, which are usually untwinned.

The Pala Chief mine has also produced some very attractive specimens of elbaite. This occurrence of both gem tourmaline and spodumene in the same pegmatite is unusual, as the two have not been found together in any quantity elsewhere in Southern California. Elbaite from the Pala Chief mine occurs in a wide range of colors, but shades of pink and red are the most common. Individual crystals can be quite large and excellent specimens can be seen in the American Museum of Natural History in New York City, the Los Angeles County Museum of Natural History, and the British Museum of Natural History in London.

The mine is reported to have been the source of numerous other minerals as well. Along with gem spodumene and tourmaline, Jahns and Wright (1951) list quartz, perthitic microdine, albite, beryl (morganite and aquamarine), bavenite, bertrandite, numerous bismuth-containing minerals including native bismuth, bismuthialte, bismutite, and bismite, and nurnerous phosphates including lithiophilite, triphylite, sickletite, purpurite, heterosite, stewartite, and hureaulite.

The pegmatite was heavily worked during the early part of its history, leaving a complex maze of tunnels on the dike. More recent attempts to reopen the mine were made by various parties in 1959, 1966 and 1976. Only limited amounts of kunzite and other minerals were found, and all efforts were short-lived.

The Pala Chief is currently owned by Bob Dawson of Temecula, California, who purchased it in the early 1990's. Dawson has recently (October 2000) improved the access road and extended one of the short tunnels which, after a distance of only 3 meters, encountered a 30 x 50 x 100-cm gem pocket which yielded several pieces of lustrous kunzite to 10.7 cm and five attractive, well-formed crystals of pink elbaite with flat, pale blue-gray caps. The tourmaline crystals are stout prisms measuring from 6.1 to 8.4 cm in length. Continued mining has uncovered additional small pockets containing pink to blue-gray tourmaline (Laurs, 2001).

Elizabeth R Mine

The Elizabeth R mine is a patented claim on a pegmatite dike located on the north side of Chief Mountain, not far from the Pala Chief mine. The mine is on the site of the former Ocean View and Hazel W prospects, which were first claimed around 1903, but there is no record of any production dating from that period (Weber, 1963). In 1973-1974 these claims were purchased by local miner and collector Roland Reed, who single-handedly drove more than 300 meters of tunnel (Sinkankas, 1997). In 1974-1975 and again in 1982 he discovered a major morganite-containing pocket. According to Foord et al. (1991) approximately 100 kg of morganite specimens were recovered, with individual crystals ranging up to 13 cm across. Reed renamed the Hazel W property the Elizabeth R in 1980. In September of 2000 Reed sold the original Ocean View mine to a group headed by Jeff Swanger and Stephen Koonce, Jr. of Escondido, California.

Another find was made in 1992, which produced what may be, according to Sinkankas (1997), the finest morganite specimen ever found in Southern California. This specimen consists of a large plate of cleavelandite, approximately 50 cm across, with seven large (up to 15 cm) morganite crystals, plus numerous smaller ones scattered about one side of the plate. The morganite crystals are lustrous and well formed, and have pale aquamarine cores. This specimen was recently sold by Reed and is now in a private collection. Overall, however., morganite-containing pockets have been rare at the Elizabeth R, and the majority of pockets encountered have produced only quartz and feldspar. Some of the quartz specimens recovered have been huge, however, weighing in excess of 100 kg.

The core zone of the pegmatite is very rich in spodumene, with large lath-shaped crystals penetrating the quartz core in a jackstraw fashion. Unlike at the nearby Pala Chief, however, all the spodumene in the Elizabeth R pegmatite appears to have been thoroughly altered to montmorillonite, and no kunzite or other gem spodumene has been recovered from the mine. According to Foord et al. (1991), minerals found in pockets in the pegmatite include quartz, perthitic microcline, cleavelandite, muscovite, tourmaline (schorl), beryl, columbite, and apatite. Numerous other phosphates also occur in the pegmatite as alteration products of primary lithiophilite. These include sicklerite, purpurite, hureaulite, phosphosiderite, strengite, stewartite, eosphorite, robertsite, mitridatite, jahnsite, fairfieldite, hopeite, and pseudomalachite. Sinkankas (1997) also reports the presence of bismuth-containing minerals including clinobisvanite, namibite, and beyerite.

In July of 2000 Reed started a new tunnel extending down-dip on the Elizabeth R property, and four months later intersected a mineralized quartz-spodumene core zone containing several small vugs which have yielded attractive elbaite--pink, blue, and bicolored pink/bluish green--plus kunzite. Interestingly, this zone is completely unlike the beryl-bearing zone previously exploited on the property; it more closely resembles the zones of tourmaline mineralization at the Tourmaline Queen and Pala Chief mines (Laurs, 2001).

Rincon District

Mack, Clark and Victor Mines

The Rincon pegmatite district is located approximately 17 km southeast of the Pala district in the Pauma Valley of north-central San Diego County. The district encompasses numerous individual pegmatite dikes, most of which are mineralogically simple. A few pegmatites show enrichment in rare elements such as lithium, beryllium, and boron and have produced small amounts of gem and specimen materials in the past (Hanley, 1951).

The best-known mines in the Rincon district are the Mack, Clark, and Victor mines, all of which were originally developed by John Mack between 1903 and 1910. None of these mines proved productive enough to sustain commercial development and, with the exception of some excavations at the Clark mine during World War II for radio-grade quartz, the properties have only occasionally been worked by amateur collectors since 1910.

The Mack mine is best known for producing small amounts of gemmy, pale blue to bluish green, prismatic crystals of aquamarine. The Clark mine has produced, in addition to quartz, small quantities of gem morganite (Sinkankas, 1959). The Victor mine is the only pegmatite in the Rincon district that has yielded any gemquality colored tourmaline. The mine is best known for producing gem-quality pencil-like crystals of blue to violet-colored elbaite, but pinks and greens have been found as well, along with a few aquamarine crystals.

During May of 1999, local property owner Brian Chuchua, with the assistance of Blue Sheppard, uncovered and collected a helvite-containing pocket on a pegmatite dike in the vicinity of the Clark mine. Well-formed, dark brown, tetrahedral helvite crystals, some over 2 cm on edge, occurred on a matrix of partially decomposed feldspar and quartz. Some specimens were heavily manganese stained, possibly by the decomposition of locally abundant primary phosphates such as lithiophilite. In all, several hundred specimens were collected from the pocket (B. Sheppard, personal communication, 1999). Much of the Rincon pegmatite district is on either Indian tribal land or private ranch land and, with the exception of the helvite find, very little mining has occurred in the district for many years.

Mesa Grande District

The Mesa Grande pegmatite district is located in north-central San Diego County, about 25 miles (40 km) southeast of the Pala district, near Henshaw reservoir. The district contains numerous pegmatites that are dispersed over a fairly wide area centered on Gem Hill (elev. 1305 m). Jahns and Hanley (1953) described a total of 26 mines and prospects that were known to have produced gem or specimen material during the earlier part of the 20th century. The Himalaya dike system has historically been the most productive pegmatite in the district, and in recent years the Himalaya mine has been the only active mine. The following description of the history and mineralogy of the Himalaya mine is abstracted from Fisher et al. (1998). The reader is also referred to Foord (1976, 1977) for more information.

Himalaya Mine

The Himalaya mine is the northernmost, and historically the most productive, of three mining properties which occupy a system of several roughly parallel, northwest-trending pegmatite dikes located on the north and east flanks of Gem Hill. Adjoining the Himalaya mine on the south is the San Diego mine, and to the south of that is the Mesa Grande mine. Since its discovery in 1898, the deposit has enjoyed intermittent production, depending largely on the economics of the gem and specimen market. During this time, however, the output of colored tourmaline (elbaite) from the Himalaya mine has been considerable and the mine has certainly been the largest producer of gem-quality and specimen-grade tourmaline in North America, and possibly the world.

The Himalaya dike system is a group of several relatively thin and remarkably continuous pegmatites that crop out along the east and north flanks of Gem Hill, dipping westward into the hillside. On the Himalaya property, the dike system consists of two major and several smaller, roughly parallel dikes that meet the surface on the southeast side of the property and curve around to the northwest across the northern flank of Gem Hill. Historic mining activities have obliterated most surface exposures of the dikes, but a total of four pegmatites are exposed along the length of the current mine access adit.

The two larger dikes each average between 30 and 100 cm thick and are referred to as the upper and lower dikes. Both are pocket-bearing and are about 12 to 15 meters apart on the Himalaya property, though they appear to converge southward and are seen in contact in the San Diego mine (Foord, 1976). lathe Himalaya mine almost all of the current workings have been developed on the upper dike. Although the lower dike has seen some development in the San Diego mine, it has been largely ignored, at least during the most recent mining activities at the Himalaya, as it produces only dark green elbaite and not the more commercially desirable pink.

Because production records are incomplete, the total production from the mine is not known, but has been estimated at over 100 metric tons of elbaite and other specimen materials (Foord et al., 1991). This is all the more remarkable considering that the main Himalaya dike is, on average, less than a meter thick. Besides its output of tourmaline, the mine has also produced well-crystallized specimens of numerous other pegmatite minerals, most notably perthitic microcline, colorless and smoky quartz, lepidolite, albite (var. cleavelandite), stibiotantalite, hambergite, apatite, beryl (morganite and goshenite), and stilbite. Compared to some other southern California pegmatites, such as those near Pala, the Himalaya dike system is depleted in phosphorous, resulting in a scarcity of phosphate minerals other than occasional apatite. The dike system is also devoid of any of the primary Li-Al silicates, e.g. spodumene (including kunzite), petalite or eucryptite, which are present elsewhere in the world in complex pe gmatites of this type.

Though the Himalaya mine was officially claimed in 1898, Kunz (1905b) reports that local Indians had prior knowledge of the tourmaline and that crystals were even occasionally found in Indian graves in the area. A perhaps apocryphal story related by Kunz (1905b), Carnahan (1960) and again by Bancroft (1984) has it that tourmaline from the area first came to the attention of white settlers when someone noticed Indian children playing with colored tourmaline crystals in the nearby village of Mesa Grande.

Details of the early operation of the mine are sketchy, but it appears that both the Himalaya and San Diego mines were originally claimed by Gail Lewis around 1898; he accomplished a limited amount of work on the surface of both properties during the next few years (Weber, 1963; Foord, 1976). In 1902 the Himalaya property was acquired by J. L. Tannenbaum, apparently using the time-honored process of claim jumping. lathe ensuing legal battles Tannenbaum was forced to pay Lewis $40,000 (a significant sum at the time) to clear the title, but was able to gain possession of the claim (Bancroft, 1984). Lewis retained and continued to work the adjoining San Diego mine.

Between 1902 and 1912 the Himalaya Mining Company, headed by Tannenbaum, produced considerable amounts of elbaite from the mine. Shigley et al. (1986) have estimated that during this period approximately 100,000 kg of tourmaline were produced by the Himalaya and San Diego mines, with a value at the time of more than $750,000. After the collapse of the local gem market, tourmaline prices remained depressed for several decades; between 1913 and the early 1950's mining activities on the Himalaya property were small-scale and sporadic.

In 1952 the Himalaya mine was acquired by Ralph Potter, who made the first attempts at systematic mining since 1912. Beginning in 1957, Potter rehabilitated several inclines on the southeast side of the property, as well as the old "Main Tunnel" which accessed the dike from the northwest. In addition, he drove several new tunnels from the northwest to reach portions of the dike below the Main Tunnel. Though no records were kept, Potter is reported to have found major pockets of elbaite in 1958 and 1963 (W. Larson, 1997, personal commmunication).

In 1963 Potter divided the property into ten shares, selling eight of them and retaining two for himself. The partnership, operating as the Himalaya Gem Mines, Inc., did a moderate amount of work, but with the collapse of the Main Tunnel portal during the wet winter of 1968-1969 underground mining ceased entirely. Some surface work was done on the east side of Gem Hill in unmined portions of the dike system.

In 1977 Pala Properties International leased the property from the partnership (Eidahl, 1977), and later purchased it outright in 1988. Under the direction of mine manager John McLean, they began an aggressive mining program that resulted in the highest level of gem and specimen production since the Tannenbaum era. Work initially focused on reopening and expanding an incline, which followed the main dike down-dip on the southeast side of the property. Beginning in 1990, an entirely new adit was driven low on the southeast side of the property in order to reach the dike at a low level. After tunneling westward for approximately 670 feet, the main dike was intersected and mining proceeded up-dip on the dike, as well as along strike to the north and south, extending into the areas previously worked by Potter and Tannenbaum.

Tourmaline production from the mine was remarkably consistent during the 1980's and 1990's, but several exceptional pockets were encountered, including the "McLean Pocket" in 1983, the "President's Day Pocket" in 1989 (Jones, 1990), the "Green Pocket" in 1993, and 'The Rainbow Pocket" in 1996 (Fisher et al., 1998).

Over the years, the main Himalaya dike has been heavily worked; remaining blocks of potentially productive ground in the upper levels appear limited. It is estimated that during the last 20 years Pala International (a corporation owned by William Larson, formed upon the dissolution of his Pala Properties International partnership with Ed Swoboda) has driven over 8000 feet of tunnel, which yielded over 2.5 metric tons of tourmaline (W. Larson, 1997 personal communication). After being worked for almost two years without any significant new finds, the Himalaya mine was closed by Pala International in 1998 and the property was leased to new operators who, so far, appear to have had little success.

Feldspars and quartz are the most abundant minerals in the Himalaya dike system, and well-formed crystals are found in most pockets. The most common feldspars in the pocket zone are perthitic microcline, and albite (var. cleavelandite). Well-formed crystals of tan to gray microcline can range in size from less than 1 cm to over 30 cm and commonly show incipient to moderate corrosion, producing a "boxwork" texture on the surface of the crystals. Most microcine crystals are twinned and well-formed crystals displaying Baveno, Manebach, and Carlsbad twin laws can be found. Well-formed quartz crystals up to 10 cm are common in the pockets and are often associated with other minerals. The color is often a pale smoky shade, though the range is colorless to almost black (morion).

Muscovite is the most common of the mica group minerals in the Himalaya dike system and is found in all portions of the dikes. Within the pocket zone, muscovite crystals usually form wedge-shaped "books" up to 4 cm in size and may be silvery to a pale yellow-green. Lepidolite is confined largely to the core zone of the upper dike and appears to be largely absent in the lower dike. In the core zone, lepidolite occurs as large masses of fine-grained, purple crystals. In pockets, lepidolite often occurs as well-formed, barrel-shaped crystals up to 3 cm long on the surface of, or slightly embedded in, other pocket minerals such as quartz, feldspars and elbaite. Epitaxial overgrowths of lepidolite on muscovite are also common in some pockets.

Elbaite crystals from pockets in the upper Himalaya dike are usually trigonal and heavily striated on the prism faces, though late-formed, pencil-sized gems are often smooth and hexagonal in cross section. Schori is abundant in the intermediate zones of all dikes, but has not been found in pockets on the upper dike. Schori crystals are, however, occasionally found in pockets on the lower dike. Crystals of elbaite found in the upper dike are almost always multi-colored. Various shades of pink and green are the most common in pocket-zone crystals from the upper dike and late-stage tourmaline overgrowths on crystals may be colorless, burgundy red, green, and/or blue-green. Reverse "watermelon" patterns (green interior, pink "rind") are common. Pink elbaite is rare in the lower dike and crystals from the pocket zone are usually dark green. Doubly terminated single crystals are common.

Beryl is relatively scarce in the Himalaya dike system. Frozen masses of both morganite and pale aquamarine have been observed in the intermediate zones of the upper dike, but pocket occurrences of beryl from the mine are uncommon. Highly etched and cavernous fragments of morganite are sometimes found in pockets. These fragments almost never show any crystal faces, but are usually quite gemmy and have a rich peach-pink color. Even scarcer are occasional well-formed, colorless crystals of goshenite beryl.

Fluorapatite is the only phosphate mineral of any abundance in the system, though Foord (1976) reports the rare occurrence of monazite and xenotime. Specimens of fluorapatite are occasionally found in pockets on both the upper and lower Himalaya dikes. Crystals are usually well-formed, simple hexagonal prisms up to 5 cm in length, and may be tabular or prismatic in habit. The color ranges from a pale pink to a deep wine-red; occasionally crystals are found that have a thin blue layer at the termination. The pink-red color is unstable, however, and will fade rapidly in sunlight to an unattractive grayish white.

Specimens of the stibiocolumbite-stibiotantalite series from the Himalaya mine are relatively scarce, but are among the finest crystals of the species found anywhere in the world. Most specimens from the Himalaya dike system appear to be the stibiotantalite end-member (Foord 1976, 1977) and typically occur as tabular to equant single crystals or clusters up to 5 cm. The color ranges from honey-yellow to reddish brown with a resinous luster. The rare minerals rynersonite [Ca[(Ta,Nb).sub.2][O.sub.6]] and fersmite are occasionally found associated with stibiotantalite as alteration products; the Himalaya mine is the type locality for rynersonite (Foord, 1976, 1977; Foord and Mrose, 1978).

Small crystals of honey-yellow microlite and darker brown uranmicrolite are often found included in other pocket minerals such as quartz and elbaite. Uranmicrolite inclusions can be identified by the radiation-induced discoloration halos in the host mineral. Late-stage secondary minerals including stilbite, laumontite, calcite and cookeite are often found as coatings on earlier formed minerals such as quartz, feldspars and elbaite. Secondary Be-containing minerals including hambergite and bavenite are occasionally found in pockets in the upper dike, probably formed at the expense of earlier beryl. Hambergite usually occurs as small porcelain-white, wedge-shaped crystals, commonly associated with other pocket minerals such as elbaite and feldspars. Bavenite usually occurs as crusts of acicular white microcrystals coating earlier-formed pocket minerals. Bavenite pseudomorphs after beryl are occasionally found (Schaller and Fairchild, 1932).

San Diego Mine

As previously mentioned, there are numerous other mines and prospects in the Mesa Grande district that may have produced some specimen or gem material during the height of the Southern California gem mining activities during the early years of the 20th century. Only a couple of these are known to have produced any volume of material, however.

Adjoining the Himalaya mine to the south is the San Diego mine, which works the same dike system. The mine was originally opened in 1899 by Gail Lewis and was worked intensively until around 1910, during which time sizable amounts of tourmaline, beryl, and quartz were produced (Jahns and Hanley, 1953). After the collapse of the local gem market in 1912, the mine was idled, and has never been reopened on a commercial scale. The mine was acquired around 1915 by Fred Rynerson who, along with several lessees, accomplished some small-scale mining during the next several decades. Projects included exploration of the dike for pollucite (as a source of cesium) by General Electric during the late 1920's and an attempt to work the mine for gem tourmaline by the famous collecting team of Ed Over and Arthur Montgomery in 1935 (Montgomery, 1997). None of these projects proved particularly successful, however.

With Rynerson's death in 1960, his son Eugene took over operation of the mine, and for approximately the next 25 years he worked the mine single-handedly. Eugene Rynerson was evidently a very secretive person and it is not known what he found in the mine or how it may have been disposed of. Failing health forced Rynerson to give up work on the mine in the mid-1980's and the property was idle until recently. In the late 1990's Rynerson's family leased the property to a partnership who were planning to jointly operate both the Himalaya and San Diego mines. Unfortunately, little work appears to have actually occurred.

Elbaite from the San Diego mine is largely identical in appearance to that from the Himalaya mine and without documentation it is impossible to tell material from the two mines apart. The amount of elbaite produced by the San Diego has never matched that of its northerly neighbor, the Himalaya, and according to Foord (personal communication, 1996), the density of pockets (and thus gem and specimen producing potential) within the core of the main dike decreases southward along the dike.

Mesa Grande Mine

Adjoining the San Diego mine to the south is the Mesa Grande mine--the southern-most mine on the Himalaya dike system. According to Jahns and Hanley (1953), this mine was worked actively between 1906 and 1909, producing an unknown amount of pink and purplish blue tourmaline, along with some morganite and aquamarine beryl. The property has been largely idle since that time, but minor amounts of black to dark green tourmaline and smoky quartz have come from recent excavations carried out by the property owner, a Mr. Forest (J. McLean, personal communication, 1997).

Esmeralda Mine

The other mine of note in the Mesa Grande district is the Esmeralda, which is located approximately 2 km west of the Himalaya on a ridge east of Temescal Canyon. This pegmatite was originally prospected by Gail Lewis between 1899 and 1904 with apparently only modest success (Jahns and Hanley, 1953). The mine was subsequently taken over by Harry Dougherty, who worked the property until 1909. During this time, the mine produced some fine specimens of morganite and aquamarine and modest amounts of tourmaline of various colors (Sinkankas, 1959). According to Jahns and Hanley (1953), most of the production from the Esmeralda came from one very large pocket found in a section of the dike where the core bulges. Many specimens from this find were sold to museums in the eastern United States and Europe. The Esmeralda mine has been idle in recent years.

Other Mines

Several other mines and prospects in the Mesa Grande District are mentioned by Jahns and Hanley (1953) as having produced minor amounts of specimen and gem material during the early part of the 20th century. These include the Cota, Bushnell, Green Ledge, Payne, and Trail mines. None of these mines appear to have been active since that time.

Ramona District

The Ramona pegmatite district consists of numerous individual pegmatite dikes exposed along the north side of Hatfield Creek Canyon, approximately 3 km east of the town of Ramona in central San Diego County. The pegmatites form a roughly parallel swarm, striking northwest and dipping moderately to the southwest. Because the pegmatites occur mostly on south-facing slopes their southwest dip gives them a fortuitous dip-slope orientation, which has allowed much mining to be done from the surface rather than underground. The Ramona district is somewhat unusual compared to other Southern California districts in that dikes in close proximity to each other often contain widely varying mineral assemblages. The district is also unique to the region in producing major amounts of gem-grade and specimen-quality topaz and spessartine.

Numerous mines and prospects were established in the district during the first decade of the 20th century, but the most productive and well known are the Little Three and Hercules mines. Both mines were first claimed in 1903 and actively worked until around 1912. Kunz (1905b) reports the production of blue and colorless topaz, spessartine, green and pink beryl, large quartz crystals, and large crystals of dark green tourmaline. Other mines worked during this period include the ABC, Black Panther, Surprise, Lookout, and Prospect mines. Most of these appear to have been idle since 1912, and the Surprise, which is located on an eastern extension of the main Little Three dike, is now back-filled with dump material (Sinkankas, 1959).

Little Three Mine

In 1951 the Little Three mine was acquired by Louis Spaulding, Sr., who began work there a few years later. With his death in 1973, the mine was taken over by his son, Louis Spaulding, Jr. Full-time mining was resumed in 1975 and the mine was worked more-or-less full time for the next 20 years by both surface trenching and underground tunneling.

In July of 1976, a major topaz and tourmaline-bearing pocket known as the "New Spaulding Pocket" was found in the main Little Three dike. This pocket was approximately 50 cm by 3 x 3 meters in size and produced an estimated 90kg of elbaite, 28 kg of topaz, and over 200 kg of large, euhedral specimens of lepidolite (Shigley et at, 1986). Several large matrix specimens were recovered from this pocket, including a 25-cm plate of cleavelandite and smoky quartz with two large, dark green elbaite crystals and two blue topaz crystals, now in the Carnegie Museum of Natural History, Pittsburgh, Pennsylvania. Several other smaller pockets were found in the vicinity of the New Spaulding Pocket; a detailed description of the find is given in Stern et al. (1986). A second major topaz and elbaite-bearing pocket was discovered in 1986. Total production from the Little Three mine has been estimated by Foord et al. (1989) to have been approximately 900 kg of elbaite, 110 kg of topaz, and 25 kg of beryl.

Besides the main Little Three dike, there are several other pegmatites on the Little Three property, including the Spaulding, Sinkankas, and Hatfield Creek dikes. Some small-scale mining has been done on these dikes in recent years, but none has ever produced significant amounts of gem or specimen material. The Spaulding and Sinkankas dikes are reported to have produced some spessartine and the Hatfield Creek dike is known for producing manganaxinite specimens (Sinkankas, 1976).

Topaz from the main Little Three dike occurs in two distinct generations. Earlier-formed crystals tend to be large (some exceeding 450 grams) and pale blue to pale green in color, often resembling those from Murzinka in the Ural Mts. of Russia. Crystals may be terminated by either a well-developed basal pinacoid {001} or well-developed first order prism faces {02} and {011} with a small or absent pinacoid. When first mined, these topaz crystals are often pale in color, but Foord et at (1989) note a tendency of many Little Three topaz crystals to darken over time after recovery. A second, later generation of topaz occurs as small (less than 1 cm), colorless crystals, sometimes doubly terminated, which are occasionally found on the surface of elbaite and other pocket minerals. Foord et al. (1989) mention the occurrence of one pocket containing topaz and green elbaite on the Hercules dike, but give no other details.

Elbaite from the main Little Three dike is usually various shades of dark green, olive-green or brown, though crystals with pale pink sections are occasionally found. Crystals are usually heavily striated trigonal prisms with simple pedion terminations. Elbaite crystals from pockets in the main Little Three dike are often associated with cleavelandite, smoky quartz, and sometimes topaz, forming very attractive specimens. Some small gem "pencil" crystals displaying pyramidal terminations have been found as well. Schorl is common in the main Little Three dike, but is not usually found as well-formed pocket crystals.

The main Little Three dike is more complex mineralogically than the Hercules dike, and is the source of numerous other, often rare, mineral species. Foord et al. (1989) reports the occurrence of native bismuth, bismite, bismutite, pucherite, cassiterite, fluorapatite, columbite group minerals, microlite, uranmicrolite, hambergite, stilbite, laumontite, and two species for which the Little Three mine is the type locality, boromuscovite (Foord and Martin et al., 1991) and a Bi-W containing polymorph of stibiocolumbite-stibiotantalite.

Hercules Mine

The Hercules mine (also called the Hercules-Spessartine mine) is adjacent to the Little Three on the north. Though the two are separate claims, they have both been worked in recent years by Louis Spaulding Jr. For many years the Hercules claim was actually owned by Buzz Gray, a well-known gem cutter, and Bryant Harris, a mineral collector. Spaulding was given permission to work the property in exchange for first rights to any gem materials recovered. During the 1970's and 1980's, Spaulding alternated work between the main topaz-bearing dike on the Little Three property and the Hercules dike. Working the dike by surface trenching, Spaulding produced a fair amount of spessartine, mostly gem rough, during this time. Foord et al. (1989) estimate that the Hercules and other nearby dikes have produced a total of around 40,000 carats of spessartine; major finds are thought to have occurred in 1976, 1985 and 1986.

Garnet of the almandine-spessartine series is common in both the main Little Three and Hercules dikes. It has not been found within pockets in the main Little Three dike, however, and most garnet of gem or specimen quality has come from the Hercules dike. Garnet from pockets in the Hercules dike is bright orange in color and compositionally is close to end-member spessartine (Foord and Kleck, 1993). Much of the spessartine from the pockets in the Hercules dike has been etched or corroded into gemmy fragments which are found in cavities in masses of cleavelandite or loose at the bottom of pockets. Lustrous, euhedral spessartine crystals are also found, often associated with other pocket minerals such as cleavelandite and schorl. These crystals usually show dominant dodecahedral {110}, trapezohedral {211}, or hexoctahedral {321} faces, or a combination of these.

In addition to spessartine, a major beryl-containing pocket (morganite, goshenite, and aquamarine) was discovered in 1985, and a pocket containing numerous large manganaxinite crystals was found in 1986 (Foord et al., 1989). By the mid 1990's excavations on the Hercules dike had become dangerously deep, limiting further surface development of the mine; the mining claim on the property was allowed to expire.

Although the main Little Three and Hercules dikes are in relatively close proximity to each other, each dike has its own characteristic mineralogy. Pockets in the main Little Three dike are known for producing fine specimens of topaz, elbaite, and lepidolite, whereas pockets in the Hercules dike have produced excellent spessartine, schorl, and occasional beryl and manganaxinite.

Tourmaline from pockets in the Hercules dike is almost always schorl and some fine specimens associated with orange spessartine and white cleavelandite have been found. Excellent specimens of this type are in the collections of the National Museum of Natural History (Smithsonian Institution) and the Los Angeles County Museum of Natural History.

Beryl is occasionally found in both the main Little Three and Hercules dikes, though most well-formed crystals appear to have come from the Hercules. Prismatic crystals of morganite, goshenite, and aquamarine up to 8 cm long have been found in recent years, mostly from one pocket in the Hercules dike discovered in 1985. Beryl crystals are often lustrous and euhedral, but highly etched crystals are also found. Foord et al. (1989) state that beryl crystals found in pockets with spessartine usually show varying degrees of corrosion while those from pockets devoid of garnet are usually pristine. While crystals of morganite from other occurrences in southern California usually have a tabular habit, Ramona morganite crystals tend to be prismatic.

Jacumba District

The Jacumba pegmatite district is located in an arid and remote region of southeastern San Diego County, approximately 100 km east of the city of San Diego, and just north of the Mexican border. The pegmatites have been intruded into metasedimentary rocks (gneisses and schists) around Tule Mountain, which is 11 km northwest of the town of Jacumba.

Crystal Gem Mine

Kunz (1905b) mentions several prospects in the Jacumba area, including one known as the Crystal Gem mine, which had, at the time, produced some spessartine and beryl. The exact location of the Crystal Gem mine is uncertain, and it is unknown whether it correlates with any of the current mining claims in the area. Little else appears to have been done in the district until late 1974, when local mineral collector Loren Beebe discovered a pocket of spodumene while prospecting the area. Sinkankas (1976) reports that the pocket yielded 24 kg of spodumene of various colors, including lilac (kunzite), blue, yellow, and colorless. One of the largest crystals from the find is now in the collection of the Los Angeles County Museum of Natural History. A claim, known as the "Beebe Hole," was established on the site, but little else appears to have been found there.

Pack Rat Mine

In 1981 Fred Stevens began working the Pack Rat mine, a claim adjacent to the Beebe Hole on the same pegmatite. Stevens worked the claim for about 10 years, producing some spessartine and apatite crystals, before selling it to the current owner, Gary Wallace. Wallace has continued to work the Pack Rat on a part-time basis. During the early 1990's he also acquired the Beebe Hole claim, which he has merged with the Pack Rat. The mine has produced an interesting suite of minerals in recent years, including pale blue to green aquamarine, alpine-like smoky quartz crystals, spessartine, danburite, columbite, cassiterite, helvite, and numerous phosphates including apatite, lithiophilite, purpurite, herderite, strengite, phosphosiderite, hureaulite, robertsite, eosphorite, frondelite and mitridatite (A. R. Kampf, personal communication, 2000). The pegmatite shows considerable potential for specimen production, and several other mining claims have been established on neighboring pegmatites in recent years. The area is , unfortunately, within the local bighorn sheep breeding grounds and is considered "ecologically sensitive" by the BLM, who are reluctant to allow the development of access roads and the use of heavy equipment. This effectively places restrictions on the scale of mining activities that can be conducted at the Pack Rat and other pegmatites in the area.

Northern Baja California

During the mid 1960's and 1970's, a number of gem-bearing pegmatites were discovered and worked in a broad region extending southward for several hundred kilometers from the area around the town of Tecate near the California-Mexico border. Much of the area is remote and sparsely populated. Roads are often more like ephemeral dirt trails, and consequently the exact location of many of the pegmatites is today far from certain. None of the pegmatites in this region has ever produced large amounts of gem or specimen materials and little work appears to have done other than casual collecting. The following are descriptions of some of the better-known pegmatites.

Chuqui Mine

The Chuqui mine is located near the small town of Rosa De Castilla, about 75 km south of Tecate. Sinkankas (1976) reports that the pegmatite here trends north-south, dips gently to the east, is approximately 3 meters thick, and consists largely of graphic granite. The pegmatite has produced tourmaline crystals up to 12 cm long, mostly black to dark purple in color. No other minerals are reported.

Mina La Verde

The Mina La Verde pegmatite is located near the village of La Huerta, approximately 48 km east of Ensenada. The pegmatite was discovered in 1964 and worked in the early 1970's by a party sponsored by the late Josie Scripps, a San Diego mineral collector and volunteer curator of minerals at the San Diego Museum of Natural History. Sinkankas (1976) reports that a series of small pockets produced microcline, muscovite, smoky quartz, some large opaque danburite crystals, and green tourmaline. The tourmaline was usually olive green, forming interesting specimens, but not of gem quality. Individual crystals formed as triangular, spray-like composites up to 12 cm long. Tourmaline also occurred as crusts of small individual crystals on the surface of microcline crystals.

Las Delicias Mine

The Las Delicias pegmatite is located near the village of El Alamo, 62 km southeast of Ensenada, along the rim of the Arroyo de Rincon. The Las Delicias is one of numerous pegmatites that stand out like ribs along the canyon walls. The pegmatite is enriched in rare elements, including lithium, beryllium and boron. Minerals such as tourmaline (schori and elbaite), lepidolite, spessartine, and beryl appear common, but are usually frozen in the dike, as pockets are relatively scarce. The mine was actively worked during the late 1960's and Sinkankas (1976) reports that some large, heavily striated tourmaline crystals were found. These have a raspberry-red core and a green outer layer; many are coated with smaller tourmaline crystals. These large crystals are highly fractured, but smaller ones are often gemmy, ranging from green to grayish purple in color. Quartz, microcline, albite, morganite, and topaz are also reported to have been found in pockets ia the pegmatite.

CONCLUSIONS

The Southern California pegmatite province has been a major world source of gem and specimen materials throughout the 20th century. Exquisite specimens of elbaite, kunzite, morganite, and other pegmatite minerals from the region can be found in most major collections, both public and private, throughout the world. Mining activity in the region has been episodic, with high points between 1902 and 1912 and from the late 1950's into the early 1990's. During these periods, the area produced significant amounts of specimen material and gem rough. In addition, the study of these pegmatites by Richard Jahns, Eugene Foord, and others has produced a wealth of scientific information and contributed greatly to the current understanding of how and why complex granitic pegmatites form.

Currently, however, mining activities are again at a low point throughout the region for a number of reasons. Depletion of the near-surface portions of many productive pegmatites means that most future attempts at mining will have to go much deeper, drastically increasing the cost of mining. Environmental regulations and property ownership issues have also conspired to limit mining, particularly on Indian tribal lands. Encroaching human development is also an issue, particularly in the area around Ramona. Some mines, such as the Stewart, White Queen, and Little Three, appear to have the potential to produce more specimens if logistical and access issues are resolved. Others, such as the Himalaya, Pala Chief, and the Tourmaline Queen have been heavily mined and are likely to be worked again on a commercial scale only if the prices of specimens and gem rough rise enough to justify further development of these mines.

Although future prospects for pegmatite mining in southern California appear limited, the province ranks among the most productive and well studied gem and rare-element pegmatite regions in the world, surpassed in recent years only by pegmatite provinces in Brazil ,Afghanistan and Pakistan. Mining activities in southern California throughout the past century have yielded a wealth of gemstones, mineral specimens and scientific information for the collector and academic communities. Specimens from the more famous and productive mines will always be prized by discriminating collectors and curators.

ACKNOWLEDGMENTS

Numerous individuals and organizations have assisted in the preparation of this article. First and foremost, the author would like to acknowledge the assistance of the late Dr. Eugene Foord, who provided many rare and unpublished documents and photos, as well as much feedback and general inspiration. Access to, and historical information on, individual mines was generously provided by many individuals, including Bill Larson and John McLean of Pala International, Blue Sheppard of Gems of Pala, Roland Reed, Byron Weege, Otto Komarek, Louis Spaulding, Jr., Paul Geffner, Matt Taylor, and Jim Clanin. Dr. Anthony Kampf of the Los Angeles County Museum of Natural History and Dr. Abraham Rosenzweig provided a useful critique of the manuscript. Dr. Kampf also supplied numerous photos of relevant specimens from the museum's collection. Logistical support was given on many occasions by Cal and Kerith Graeber, and by Jim Walker and Mary Fong Walker. Numerous photos of mining activities taken by the late Josie Scripps wer e provided by Cal Graeber. Photographic assistance with specimens was provided by Jeff Scovil.

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Author:Fisher, Jesse
Publication:The Mineralogical Record
Geographic Code:1U9CA
Date:Sep 1, 2002
Words:16432
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