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Zagi Mountain: Northwest Frontier Province Pakistan.

Zagi Mountain and related sites near Peshawar on the border between Pakistan and Afghanistan have recently begun to produce what are probably the finest specimens of bastnasite, xenotime, and baotite known. The minerals occur in alpine-type veins in alkali granite gneiss of the Warsak igneous complex.



New York had been having a typically hot and humid August day when I (HO) boarded the 747, but the fierce heat I found when I arrived in Peshawar, Pakistan was truly shocking. It had been only a month since my last trip, but I was eager to see my good friends and associates, some of whom I had known for over 30 years, or more than half my lifetime!

Peshawar, the provincial capital of the North West Frontier Province, was the first stop on what promised to be a most exciting adventure. For years, the city has been a center for trade in the minerals of northern Pakistan and Afghanistan, the latter country lying only 30 miles to the west, over the Khyber Pass. As early as February 1999, very fine crystals of bastnasite and other unusual minerals had begun to appear on the market in Peshawar. They were reportedly found in Shinwaro, "high in the mountains" of Kunar in Afghanistan. I had been told not only that the crystals were difficult to find, but also that getting to this very dangerous area took many hours of arduous hiking. Various dealers, including myself, Dudley Blauwet of Mountain Minerals International (Moore, 2001a; Moore, 2001b), Francois Lietard, Andreas Weerth, and several Pakistani dealers (Moore, 2002; Polityka, 2002) had already brought out small lots of bastnasite crystals. At the end of 2001 the true locality was at last revealed: Zagi Mountain, only about 30 km (20 miles) northwest of Peshawar, very easy to reach by car and foot. Instantly I decided to go there and assess the potential of the locality.


Peshawar, a bustling town of about 30 square miles and 750,000 people, lies on the west side of the Peshawar sedimentary basin in western Pakistan, at an altitude of about 300 m (1000 feet). The topography is nearly flat, and the region immediately around the city produces no mineral specimens. Because of the influx of a huge number of Afghan War refugees in the past 30 years, Peshawar has become very overcrowded, and it is certainly one of the world's most polluted cities. The dense, uniform blanket of photochemical smog lying over it is produced by unregulated cooking fires, by poorly tuned automobiles and trucks, and most of all by the most popular mode of transport, the "rickshaw." This vehicle is nothing more than a boxlike attachment to a Vespa-type motor scooter. The scooter is powered by a small two-cycle engine, usually fueled with low-grade petrol sometimes adulterated with kerosene and always mixed with large amounts of often reused motor oil. When started up or accelerated, the rickshaw's motor belches a huge cloud of blue smoke.


The preferred and traditional dress in the Peshawar area is the shalwar kameez: a pair of extremely baggy pants secured to the torso by a woven drawstring, and a shirt that ends somewhere below the knees. I started wearing the shalwar kameez after 9/11 to present a lower profile, but a much-appreciated side benefit is the comfort which the outfit provides on humid summer days when temperatures can exceed 120[degrees] F. Beards, along with turbans and other head coverings, are commonly but not universally worn.

In this area of Pakistan the purdah ("curtain") system is observed fairly strictly. A girl can walk around until about age 12, after which she retreats to the sanctity of her family's house. Women rarely venture into the city, and when they do they wear burqas or chaddars which envelop them completely, with a cloth mesh covering the face. In this male-centered society, almost all duties outside the home, including shopping for clothing and food, fall to the man.

Eating can be a perilous adventure. Food is available in the openair markets and in the shops (many "shops" are just pieces of covered alleyways crammed between buildings), from street vendors, and in restaurants. Some food items are safe and some more-or-less safe, but some are "death sentences" for weak Westerners whose systems haven't built up the required immunities to the wide varieties of microbes present. Open sewers in gutters alongside the road add to the unhygienic conditions. The modern streets have grates over the sewers, but flies and foul odors pervade some areas nevertheless. I always marvel at the hydro-engineering that keeps the system flowing despite the flatness of the area.

Walking through the narrow markets, one can smell the rich aroma of freshly baked naan, or roti, the flat bread that is a staple of the Pakistani diet. The breads are baked in a large, wood-fired, urn-shaped clay oven sunk into the earth. When you order one of the breads, the baker moistens a flattened lump of sourdough and sticks it onto the inside wall of the oven above the fire. After a few minutes have passed and the baking is complete, the baker uses a long iron hook to extract the roti with an elegant motion. The mouth-watering aroma promises a most delicious and safe culinary delight.

One is offered a good variety of meat, except pork, the eating of which is forbidden by the Muslim religion. The most common and popular meat is mutton, taken from the fat-tailed sheep native to the area. When the tail is cooked, its store of fat is converted to flavorful cooking oil. A typical restaurant in the bazaar area has its own butcher and its own cook. The butcher cuts the meat and sells it at a price fixed by the government. Since this price is relatively inflexible, the haggling involved in purchasing the meat is for the quality (or cut) that you are offered--the butcher trying to put in extra bones and gristle and the consumer trying to get only the choicest loin chops. After the deal is made, the meat is given to the cook, either to be prepared in a wok-shaped pot (karai) or to be put on skewers and grilled over charcoal. Since it would be possible for the cook to substitute a piece of inferior meat for the choice cut already bargained for, he is watched by his customers until the meal is cooked and delivered to the table. The stoves over which the meat is prepared are fired by wood logs up to 6 feet long. As its end burns the log is simply pushed further into the fire, eliminating the need to chop the wood, thus saving labor and time.

It is advisable not to buy one of the numerous skinned chickens that hang in the dusty air for hours until cooked and consumed. The locals have no problem eating these, but I have become violently ill almost every time I have tried one. It is much better to purchase live poultry from a street vendor, have it slaughtered, and take it immediately to your favorite restaurant to have it cooked as you desire. Purveyors of dairy products (such as the custard seller, ice cream man, and yoghurt merchant) are prone to deliver a dose of gastroenteritis with their wares. It is much safer to buy fresh cheese, now usually sold wrapped in plastic foil instead of the newspaper used years ago (when one could "read" the cheese from the transferred newsprint).

The city is roughly divided into three sections; the one that most interests the mineral dealer is the Old Town, which includes the Namak Mandi (literally "salt market") and the Sarafa Bazaar or Gold Market. Here are the mineral stores and mineral dealers, with stacks of wooden flats reaching to the ceiling in the backs of the dusty shops. The occasional fine or rare specimen might be found in one of the crates or bags, so it is necessary to search through tons of inferior pieces and outright junk. Because the minerals arrive here after having passed through many hands, they are usually accompanied by only partial--or totally false--information regarding their origin. Sometimes accurate locality information can only be determined by persistent detective work, including questioning and re-questioning the dealers and analyzing their often ambiguous answers. For example, the world's best chloritoid was at first said by one dealer to have come from "the Northern Areas," and said by a few others to have come from "Nuristan, Afghanistan." The preponderance of "Nuristan" in the dealers' reports means that I must take it as correct until I meet someone who found the material himself and can testify otherwise.

Some of the dealers are very observant but not very knowledgeable mineralogically; thus, when they notice species or crystal habits they have not seen before, they assume them to be rare and valuable. One might find a $500 price on a fluorite that would cost $5 if it came from any non-Pakistani locality. The asking price depends on how much the dealer paid, how big his bills are, how rich you look, how interested you seem (don't look interested!), and any number of other factors, perhaps including the phase of the moon.

Most larger lots and finer specimens are purchased through a commission agent. I work with an agent who is able to make much better deals for me than I would be able to make on my own. The broker and buyer visit the seller's shop and, after a lengthy exchange of polite inquiries about health and family, and after the obligatory cup of kava (green tea), the sellers might start negotiating their bottom line among themselves, exchanging finger signals under a shawl or cloth to insure the secrecy of their price. Then, using the same method in order to keep their lowest price hidden from me, the buyer, they communicate the figure to my broker. If the asking and bid price are far apart, the broker must slowly and diplomatically nudge the asking price lower and the offer higher until he thinks an agreement can be made. When he feels that both parties are near agreement, he clasps the hands of seller and buyer, pats them three times, and announces the non-negotiable binding price.


There are several variants on the name of the locality, the main ones being Zagi, Zaga, Zagai, and Zaguh. Dudley Blauwet prefers the spelling "Zegi" because generally a long a or ay sound in Urdu is transliterated as an e, and long e sound is transliterated as i. The locality is pronounced "Zaygee" by some of the local people.

Zagi Mountain is located about 5.5 km southeast of Warsak Dam on the Kabul River, in the Peshawar District of the North West Frontier Province of Pakistan, just a few miles from the Afghan border. The Warsak Dam is a major producer of hydroelectric power in western Pakistan. The area is adjacent to the Khyber Agencies, a Federally Administered Tribal Agency (FATA). (In fact, some of the locals claim that Zagi is in the Khyber FATA, not in the North West Frontier Province--Dudley Blauwet, pers. comm. 2003.) Despite the phrase "federally administered," the central government has very little real power in the FATAs, which are ruled in effect by the local jirgas, or tribal councils. A number of small villages are within a few kilometers of Zagi; Mullagori village is sometimes mentioned on labels. There are several villages by that name in the area; the largest is about 7 km southeast of Zagi, on the main road to Peshawar.

Zagi Mountain is actually a low hill covering an area of about 3 X 5 kilometers and rising about 150 to 200 meters above the surrounding plain. It is one of the first foothills of the rugged mountain range separating Pakistan and Afghanistan. Although Zagi Mountain has produced most of the bastnasite and other rare minerals, a number of matrix specimens have come recently from Tor Ghar or Torghur (Black Mountain), a ridge northwest of Zagi and south of the Kabul River in the Khyber FATA. At the time of this writing, this second locality has not been visited by any Westerner. Specimens from Tor Ghar are characterized by hard, undecomposed matrix of the same alkali granite that occurs at Zagi. The specimen on the cover of the Mineralogical Record, November-December 2002, is probably from Tor Ghar rather than Zagi. Spera Ghar, and Tora Mena, other mountains in the Khyber FATA, have begun producing specimens as well. Specimens of uncertain locality can be labeled "Warsak alkali granite, Warsak district, Pakistan."


Because Zagi Mountain is located near (or possibly in) the FATA, and therefore lies outside the jurisdiction of the central Pakistan government, special precautions had to be observed for my visit. The first order of business was to contact the landowner of the site and surrounding area. By good fortune I found that my export agent lived in a neighboring village and knew the owner well. Connections mean everything in this part of the world, and the friendships I have nurtured during my 35 years of going to the area proved to be a great advantage.

In this part of the world, preparations--however simple--take days to complete, and this trip was no exception. We were to travel with an entourage which included armed bodyguards. Finally, on a bright and humid day, the hottest of my trip, our party of five departed from Peshawar on a road leading northwest and met a second party of four on the way. Arriving in Hammedabad, near the village of Kafur Dheri, we were warmly greeted by the landowner, Mr. Abdul Kaduss, and his son, Ali Khan. Abdul kindly offered us the use of his pickup trucks and several bodyguards. After what seemed an eternity of tea and chitchat the guards arrived, armed with AK-47's and M16's, and soon we were on our way!

After a twenty-minute ride in a caravan of pickup trucks we discovered that the easy road into the area was blocked by flooding, and we were forced to double back and find another route. It quickly became clear that erosion on this alternate route would make it impossible to continue the journey by vehicle: we would have to proceed on foot in the 120[degrees] temperature. We crossed a boulder-strewn dry wash, climbed the opposite bank, and entered a village. I was advised to keep silent, since we were going through Abdul Rehman Qila (Fort), an Afghan refugee village established during the early days of the Soviet-Afghan war in the 1980's; for a while this had been the training camp of Gulbadin Hekmatyar, a powerful Afghan warlord. Heckmatyar is the leader of the anti-Soviet (and later anti-Taliban) mujahideen group Hizbi-Islami, which was heavily supported by the United States during that conflict. Now, however, Heckmatyar, an Islamic extremist opposed to the Karzai government and the American presence in Afghanistan, is being sought by American Special Forces in the area.




Just after leaving the village we sighted our goal--Zagi Mountain. After passing some sugar cane fields and fording a small stream we finally reached the diggings: the place was so hot that even the rocks seemed charred. The bastnasite and accompanying minerals are found over a wide area in collapsed pockets in the heavily weathered rock and in the alluvium associated with it. Specimens have been found in alluvial gravel up to 1 km from the foot of the mountain.

Most of the people digging for minerals at Zagi Mountain are from Abdul Rehman camp. Many of them once worked in a nearby marble-processing facility which has recently been closed because of a dispute over charges for electric power between the Khyber Tribal Agency and the Pakistani Government. Digging for bastnasite at Zagi Mountain began around late 2000 and increased tremendously in early 2002. The miners live in the camp and work the deposit during the cooler weather. Often, two or three generations of the same family work in groups of six to 15 people, digging with sticks, iron rods and shovels; the groups may include children as young as eight. The labor is intense and the conditions harsh; the returns are small, but usually are enough for the miners to survive on. My agent and I looked through the miners' treasures and were able to purchase a few specimens that will remain with me as souvenirs of my great adventure.

As of February 2004 there has been no appreciable collecting for six months at Zagi Mountain--a local chieftain with some measure of control over the digging site and/or over the diggers has forbidden it. The future of Zagi Mountain as a productive mineral locality seems at the moment quite uncertain.


I traveled to Zegi Mountain in June, 2002, and along with bodyguards hiked to the top of the mountain, which is an area of interest to archaeologists as well as mineral collectors. There are many indications that the area was inhabited by the Ghandara civilization, a pre-Islamic Buddhist culture that flourished here ca. 500-200 BC. On strategic high points on the mountain are small fortifications, originally unearthed by antique collectors and still preserved, as well as a series of stone steps leading from the south ridge past a dolphin-shaped outcrop called Rabab ("guitar") Ghunday to the summit, where there are the remnants of a Ghandarian fort called Naway Ghad. As this is the first mountain outcrop rising above the flat Kabul River plains below, it was obviously of strategic importance. Unsubstantiated reports suggest that some bastnasite beads, attributed to the Ghandarian culture, were unearthed about six meters below the surface. In the last two years several heads of statues have been found around Zegi. Trained archaeologists have not worked the site, so collecting is not systematic or organized, and potentially useful archaeological information has probably been lost.


In May, 2003, while I was in Peshawar, I met a retired major of the Frontier Corp from the Tor Ghar area, who has prospected for minerals there for the previous seven years. He said the locals preferred the term Tor Pattay (literally "Black field mountain") and that the area had been a wheat field years earlier, but is not now being farmed. There is a drivable road that approaches to within a one-hour walk from the foot of the mountain. The final village on the road is called Paindi Lalma. As you start the walk you pass by a mountain called Tamber Ghar en route to the Rambat Nala (Nala is a narrow valley), a major drainage for Tor Pattay. A secondary route up the mountain is called the Loya Nala (Big Nala in Pushtu). There the Frontier Corp Scouts have set up a picket. The very top of Torr Pattay is called Sher Sar ("Lion's Head" in both Pushtu and Urdu). Years ago wild lions inhabited this area.

Very early in the mornings the local village women travel to the upper reaches to gather grass for animal fodder and wood for cooking, returning by about 10:00 or 11:00 am. By custom, even local men are not allowed to go up the mountain for mineral exploration until all of the women have returned.


Much of northern Pakistan, including the Zagi Mountain region, lies in the foothills of the High Himalayan Crystalline Zone, between the Main Boundary Thrust and the Main Mantle Thrust (DiPietro et al., 1999; Pogue et al., 1999), a region characterized by multiple east to northeast-trending thrust faults formed during the collision of India with south Asia in the Cenozoic. The geology is extremely complex on both large and small scales, and much of the region has not been mapped in detail. The bedrock at Zagi Mountain is part of the Warsak igneous complex (Ahmand et al., 1969; Kempe, 1973; Khan, 1990), which is itself part of the Peshawar plain alkaline igneous province, a group of alkaline granites, syenites and nepheline syenites which crop out around the margins of the Peshawar basin. Prior to about 350 Ma (million years ago), what is now south Asia was part of the supercontinent of Gondwana and was connected to southern Africa. Roughly 300-350 Ma, "Cimmeria" (now Iran, Afghanistan, and Tibet) split away from Gondwana and drifted north to collide with Asia. During this interval of rifting, the rocks of the alkaline igneous province were intruded (Pogue et al., 1992). Much later, in the Cenozoic, the Indian plate, including what are now India and Pakistan, started to drift northward, eventually to collide with Asia and form the Himalayas. During the collision, about 40-45 Ma by K/Ar dating, the earlier intruded igneous rocks were heated and metamorphosed to greenschist or lower amphibolite facies. The formation of the mineral-bearing veins probably postdated the peak of metamorphism; K/Ar dating of the pocket feldspars would be necessary to establish the time of the first stage of pocket development.

The principal rock of the Warsak igneous complex is a medium-grained, gneissic alkaline granite (Kempe, 1973) composed of microcline with minor albite, quartz, aegirine, riebeckite and astrophyllite. The gneissic lineation is imparted by the alignment of riebeckite and aegirine needles and is considered by Ahmad et al. (1969) to be flow alignment formed during intrusion rather than a metamorphic texture. The most common accessory minerals are ilmenite, zircon and fluorite. The bastnaesite-bearing veins are in the alkaline granite.

Zagi Mountain is situated in an outlier of the main exposure of the alkali granite. Understandably, mineral dealers are reluctant to bring geological samples instead of salable mineral specimens back by air and through customs, so the matrix of only a few specimens could be examined for this report; this matrix is gneissic riebeckite granite. Matrix specimens of any of the crystallized minerals are rare; the majority of specimens are single crystals found loose in the decomposed rock or in the alluvium of stream beds. The relative abundances of the minerals of the locality are almost impossible to judge, as there is a high degree of selectivity on the part of both the miners and the buyers of specimens in favor of unusual minerals, and some minerals are found only in restricted areas.

Although some dealers have said that the crystals occur in pockets in alkaline pegmatites, the pockets more nearly resemble alpine veins in a number of ways: alpine veins typically occur in gneissic rocks like the rocks at Zagi, but pocket pegmatites are more typical of coarse-grained, massive intrusive rocks; there is no development of pegmatitic textures such as graphic intergrowths or sudden coarsening of grains in the rock on the walls of the pockets; the common feldspar is translucent adularia, characteristic of alpine veins, rather than the more opaque perthitic microcline found in pegmatite pockets; and finally, the rare minerals are more typical of alpine veins than of pegmatites.




All the minerals listed in this report were confirmed by X-ray powder diffraction analysis (XRD), using a computer-controlled diffractometer operating in step-scan mode. Identifications were made using search-match software and the 1990 ICDD (International Centre for Diffraction Data) powder diffraction data set on CD. Some identifications, particularly of the feldspars, were supported by optical examination using polarized-light microscopy (PLM). Selected samples were mounted on glass discs, polished, carbon-coated, and analyzed chemically by energy-dispersive spectroscopy (EDS), using a JOEL JSM6335F field-emission, cold cathode SEM, operated at 15Kv and 12.5[micro] with a 12.5-mm working distance. Spectra were gathered with a PGT light-element-capable analyzer and refined with the IXRF program EDS 2000, which uses a standardless ZAF analysis routine. The instrument is housed in the Department of Physics, University of Delaware, and operated by Gerald Poirier.

The lack of appropriate standards renders the analyses only semi-quantitative; however, experience shows that the ratios of heavier elements derived by the data-reduction program are quite accurate, but that the proportions of light elements (S and below) are less reliable. Fortunately, most of the minerals of interest at Zagi can be characterized by the presence and proportions of heavy elements such as Ce and La, or by the presence or absence of lighter elements such as P.

Aegirine NaFe[Si.sub.2][O.sub.6]

Although common in the alkali granite, aegirine appears to be rare in the alpine veins. Small green blades that occur sparsely in quartz crystals are aegirine, and recently a few dark green, short prismatic, single crystals and 4 to 5-cm crystal groups have turned up. The individual crystals measure 1 to 2 cm. They do not have attached granite matrix.

Albite NaAl[Si.sub.3][O.sub.8]

Albite is less abundant than the potassium feldspar microcline; it occurs as tabular, twinned crystals up to 1 cm, associated with microcline and quartz. In specimens studied, it is white and less translucent than microcline. It does not fluoresce. In PLM it can be distinguished from microcline by its higher indices of refraction and sharper twin lamellae. Like the microcline, the albite has almost pure end-member composition, with very little K or Ca.

Astrophyllite (K, Na)[.sub.3](Fe, Mn)[.sub.7][Ti.sub.2][Si.sub.8][O.sub.24](O,OH)[.sub.7]

Straw-yellow to pale reddish brown blades of astrophyllite are abundant as inclusions in quartz crystals. The fibrous, golden-yellow needles and fur-like swarms that are observed as inclusions in microcline, xenotime, bastnasite and other minerals are also astrophyllite rather than rutile. Free-standing astrophyllite crystals have not been observed. A pale reddish brown blade contains K about five times Na, with major Fe, minor Mn, Nb and Ta, and trace Zn.


Baotite [Ba.sub.4][Ti.sub.4](Ti,Nb,Fe)[.sub.4] ([Si.sub.4][O.sub.12])[O.sub.16]Cl

One of the recent surprises at Zagi has been the discovery of the extremely rare silicate baotite, as black to greenish yellow crystals to 4 cm, with adamantine to resinous luster. These are among the best crystals of baotite known--specimens from the type locality at Baotou, China are reportedly up to 10 cm (Peng, 1960) but have not been seen in the West. The Zagi crystals are short to long-prismatic and striated parallel to the c-axis, with simple low-angle pyramid terminations. Baotite is tetragonal, but the crystals are commonly so deformed as to appear monoclinic, very different in appearance from the beautifully formed crystals of xenotime, which is also tetragonal. Prismatic crystals of rutile are rarely associated with baotite. No matrix specimens are yet known. Baotite is another mineral of restricted occurrence, and as of this writing (June 2003) no specimens have been found for almost a year.





Bastnasite-(Ce) (Ce,La)C[O.sub.3]F

Bastnasite crystals from Zagi are undoubtedly the largest and finest ever found. They are blocky to tabular hexagonal prisms and plates of a medium-brown to rich orange-brown color, and with dull to vibrantly glassy luster. The crystals are generally sharp and crisp, though some are rounded slightly along the edges. Crystal size ranges from 1 to 2 cm, but some of the finest crystals are up to 6 cm. The prism and pinacoid forms are dominant, but many crystals are also modified to some extent by low-angle pyramidal faces. These crystals range from opaque to translucent to beautifully transparent; in fact, some gemmy fragments have been faceted into attractive gemstones. A recent (May 2003) find of bastnasite yielded exceptionally lustrous, complex crystals, some on friable matrix, with associated fluorite. The area on the north side of Zagi Mountain where these crystals have been found is referred to by the collectors as Berrudge Ghundai (or Bheruj Gunday), or "Tourmaline Hill," tourmaline being the term used for any dark, non-quartz mineral. As noted above, crystals on fresh matrix, including the one on the cover of the November-December 2002 Mineralogical Record, are more likely to be from the Tor Ghar area than from Zagi Mountain.






Chemically, the bastnasite contains both Ce and La, with Ce roughly 2.5 to 3 times as abundant as La in samples examined. Other rare earths were not noted. The bastnasite and other REE minerals are slightly radioactive, indicating the presence of trace U or Th.

Eudidymite ([Na.sub.2][Be.sub.2][Si.sub.6][O.sub.15]*[H.sub.2]O)

At the 2003 Tucson show (Moore, 2003), Andreas Weerth had a few loose samples identified as eudidymite, in thin, transparent, platy crystals and cleavage fragments, colorless to brownish white, to 5 cm. He cited them as being from near Mullagori village at the foot of Zagi Mountain, near the Warsak Dam in the Tribal Areas of Pakistan. The lot included many of the confirmed Zagi species. No sample from Herr Weerth could be examined for this report. Other purported eudidymite specimens turned out to be albite.

Fluorite (Ca[F.sub.2])

Fluorite occurs in green cuboctahedral crystals to 4 cm. They fluoresce bright blue under longwave ultraviolet light, and bright blue with persistent green phosphorescence under shortwave ultraviolet light.



Genthelvite (Zn,Fe,Mn)[.sub.4][Be.sub.3](Si[O.sub.4])[.sub.3]S

Genthelvite has been found in sharp, yellow to dark reddish brown tetrahedral crystals to 5 cm, with one exceptional 12-cm crystal that weighs in excess of 2.3 kg and thus by itself constitutes a significant fraction of the world's known genthelvite! This large crystal displays both the positive and negative tetrahedrons, with the negative tetrahedron extremely rough and stepped. The crystals have all been found loose; significant matrix specimens are unknown.




Chemically, all specimens analyzed are genthelvite, with Zn > Fe + Mn. A distorted yellowish crystal has [Zn.sub..98][Mn.sub..02][Fe.sub.<.01], and a dark reddish brown crystal has [Zn.sub..68][Mn.sub..16][Fe.sub..17].

Grossular [Ca.sub.3][Al.sub.2](Si[O.sub.4])[.sub.3]

Grossular in lustrous, dark honey-colored crystals to 3.5 cm, showing the dodecahedron, tetrahexahedron, and minor rough (and very unusual) cube faces occur in the Mohmand FATA about 30-50 km (20-30 miles) from Zagi, but labels on some marketed specimens have attributed them to Zagi Mountain, apparently to enhance their value. Associated minerals include minor diopside and traces of chlorite. A few cut stones of several carats have been offered as bastnasite. Cloudy, pale orange-brown crystals of grossular to 5 cm, some associated with pale green diopside blades, are reportedly from Zagi, but are identical in appearance to ones from a locality in the Khyber Agency, close to the Afghan border and about 20 km distant.

Hollandite Ba(Mn,Fe)[.sub.8][O.sub.16]

Black botryoidal crusts of manganese oxides occur widely at Zagi, coating other minerals. They are probably weathering products rather than part of the hydrothermal assemblage. One sample gave an XRD pattern that is a fairly good match for hollandite. Another, poorer, pattern is a fair match for cryptomelane, K[Mn.sub.8][O.sub.16]

Ilmenite [Fe.sup.2+]Ti[O.sub.3]

Ilmenite occurs in a number of habits: (1) as brilliant, sharp plates to 1.5 cm, both loose and on matrix with quartz and microcline; (2) as thick tabular crystals to 2 cm with brilliant terminations and pitted rhombohedron faces on matrix; and (3) as thin, composite plates up to 5 cm across, somewhat resembling iron roses. One such iron rose group has epitaxial rutile crystals about 5 mm by 12 mm forming six-rayed stars, as on Swiss hematite specimens. EDS analysis of the second type by Bart Cannon, of Cannon Microprobe in Seattle, on samples supplied by Dudley Blauwet, show that it is a manganoan ilmenite, with Fe:Mn about 3:1. Ilmenite in plates to 5 cm embedded in quartz are reportedly from Zagi, but the specimens are not from the veins in the alkali granite.

"Limonite" Hydrous iron oxides

Yellow to orange weathering films and crusts of poorly crystallized iron hydroxides are common at Zagi. Although it was hoped that some might prove to be secondary Ce minerals, none has been confirmed as anything but limonite. Limonite also occurs widely but sparsely in the veins as pseudomorphs after pyrite crystals. The crystals are pyritohedral and range up to about 1 cm.

Microcline (adularia) KAl[Si.sub.3][O.sub.8]

Microcline is the common feldspar in the granite and in the veins; it is the most widely distributed silicate species at Zagi, coating most matrix specimens. It occurs in several habits: (1) most commonly, as crystals with the distinctive adularia morphology, with the prominent diamond-shaped prism {110}; (2) as flattened, arrowhead-shaped Carlsbad twins; and (3), occasionally, as crystals with the usual microcline morphology, similar to Colorado amazonite. The crystals typically measure a few millimeters but can reach 5 cm. The smallest crystals are nearly colorless and transparent, with lustrous faces; larger crystals are milky and translucent. Many are crowded with minute, golden needles of astrophyllite. Adularia is commonly termed orthoclase, and is usually a mixture of domains with different degrees of internal order (and therefore a mixture of orthoclase and microcline), but the feldspar at Zagi is identified as microcline because all samples examined under the polarizing microscope showed grains with crosshatch (combined albite and pericline) or spindle (deformed albite) twinning, both of which are characteristic of microcline. In addition, the XRD patterns of samples more closely match microcline than orthoclase, although the two patterns are similar. Microcline in both the veins and the granite fluoresces a characteristic dull red. EDS analysis showed that the microcline is almost pure KAl[Si.sub.3][O.sub.8], with very little Na. This is usual in microcline adularia.

Parisite-(Ce) Ca(Ce,La)[.sub.2](C[O.sub.3])[.sub.3][F.sub.2]

Parisite is found in medium-brown hexagonal-tabular crystals to 3 cm, and also as epitactic overgrowths on bastnasite crystals. At the 2002 Tucson show, Moore (2002) saw a 6-cm crystal of deeper honey-brown bastnasite with a paler brown outer layer, which he was told was epitactic parisite. Microprobe analysis by Bart Cannon of Cannon Microprobe in Seattle on samples supplied by Dudley Blauwet reveal that some crystals are indeed zoned, part parisite and part bastnasite. One 8-mm equant bastnasite shows a belt of slightly paler parisite; Dudley Blauwet has seen fewer than half a dozen such pieces. One analyzed sample of parisite contained both Ce and La, in the ratio of 2.78:1, similar to the ratio in bastnasite.






Quartz Si[O.sub.2]

Quartz is a constituent of the gneiss and also occurs in colorless to smoky, gemmy, lustrous crystals to 10 cm, and in 15-cm aggregates of individual crystals to 5 cm; crystals have been found at Zagi, at Tor Ghar, and at Spara Ghar, a hill between the two localities. Most quartz crystals have inclusions of black acicular riebeckite, or of golden astrophyllite, and some have free-standing, finger-thick rutile crystals on and below the quartz crystal faces. Rarely, well-formed crystals of xenotime or bastnasite to 5 mm occur as inclusions in quartz crystals.

Rhabdophane-(Ce) (Ce,La)P[O.sub.4]*[H.sub.2]O

Rhabdophane was noted as a yellowish tan, fine-grained, compact coating on a 3-cm cluster of bastnasite crystals. The rhabdophane appears to be a replacement of the bastnasite rather than an incrustation or overgrowth, and has roughly the same Ce:La ratio.

Riebeckite [Na.sub.2]([Fe.sup.2+],Mg)[.sub.3][Fe.sub.2.sup.3+][Si.sub.8][O.sub.22](OH)[.sub.2]

Riebeckite is a constituent of the granite gneiss bedrock. It is also found as acicular inclusions in a number of minerals, particularly quartz and titanite, and occurs in bladed crystals to 8 cm. Riebeckite is the commonest black mineral in the deposits. An analyzed grain is close to pure riebeckite, but has some K and Ca as well as Na, and minor Mn and Mg substituting for Fe, as well as trace Al, probably substituting for Si.


Rutile Ti[O.sub.2]

Rutile occurs in prismatic crystals as long as 3.8 cm, associated with quartz and microcline. A slightly abraded sixling twin about 2 cm across that appears to be a complete floater was found in a stream bed. Rutile has also been found growing epitaxially on ilmenite, as mentioned above. EDS analysis of a typical crystal indicates 1.8 to 3.7 atomic % Fe, as well as several weight % (but only about 1 atomic %) Hg (mercury), which is not reported in standard textbooks as an observed trace element in rutile.

Thorite ThSi[O.sub.4]

A single irregular, opaque orange-brown crystal of thorite has been found. It has bits of granite adhering to all surfaces, suggesting that it is from the granite rather than being a later pocket mineral. It is radioactive, and the XRD pattern has broad, low peaks, indicating that the structure is partly metamict (broken down by internal radioactive bombardment).

Titanite CaTiSi[O.sub.5]

Titanite forms yellow to orange, commonly twinned crystals to 4 cm. The crystals are generally opaque and somewhat crude in form, but some superb, yellow to orange-red, translucent to transparent crystals were found recently at Zagi. Needles to slender prisms of riebeckite commonly penetrate the titanite crystals.

Xenotime-(Y) YP[O.sub.4]

Xenotime is restricted in its occurrence and has been found in only a few areas. It forms prismatic, tetragonal crystals from 1 mm to 6 cm; many of the larger crystals are composite, with numerous stepped faces. One 3.5-cm composite crystal shows a distinct twist about the c axis, like a gwindel. Some are among the largest and arguably the finest crystals of xenotime known. Microcrystals are lustrous, pale yellow and transparent. Larger crystals are slightly translucent and many show a remarkable color change, from pale yellow brown or brownish green in daylight to salmon-red in incandescent light. One matrix specimen includes 1 to 2-mm crystals of xenotime, quartz, and microcline; all three minerals have inclusions of fine yellow needles of astrophyllite, suggesting that crystallization of xenotime was contemporaneous with that of the other minerals. Xenotime crystals look remarkably like zircon, with which it is isostructural, but are paler in color and softer.




The one xenotime sample analyzed is chemically more complex than the bastnasite or parisite. It contains slightly smaller REE (rare earth element) cations, including dysprosium (Dy), gadolinium (Gd) and europium (Er), as well as yttrium (Y), in the proportions [Y.sub..73][Dy.sub..17][Er.sub..06][Gd.sub..04].

Zircon ZrSi[O.sub.4]

Transparent, orange-brown pieces of zircon showing alluvial abrasion have been observed by Dudley Blauwet mixed in with parcels of bastnasite cutting rough in Peshawar, but there are no confirmed specimens from Zagi; zircon is uncommon as a cavity mineral. Microscopic, accessory zircon grains do occur in the massive alkaline granite gneiss.


Zagi Mountain can still be worked (barring local political problems) and may continue producing specimens for a considerable time, especially if work continues into the less altered bedrock. The new localities in the Khyber FATA have just begun to be developed, and their existence suggests that bastnasite-bearing veins may be widespread in the Warsak alkali granite. Rocks very similar to those at Zagi crop out on the eastern side of the Peshawar basin, and the Peshawar plain intrusive complex also includes a number of carbonatite bodies, so the potential for the discovery of additional productive or interesting occurrences in the region is substantial. However, finds are sporadic and in some cases the specimen may be unique. It appears unlikely that specimens as fine as the best of what has already discovered at Zagi Mountain will ever be abundant.
Table 1. Minerals from Zagi Mountain.

  Fluorite          Ca[F.sub.2]
  Hollandite        Ba(Mn,Fe)[.sub.8][O.sub.16]
  Ilmenite          [Fe.sup.2+]Ti[O.sub.3]
  "Limonite"        Fe(OH)[.sub.3]
  Rutile            Ti[O.sub.2]
  Bastnasite-(Ce)   (Ce,La)C[O.sub.3]F
  Parisite-(Ce)     Ca(Ce,La)[.sub.2](C[O.sub.3][.sub.3][F.sub.2]
  Rhabdophane-(Ce)  (Ca,La)P[O.sub.4].[H.sub.2]O
  Xenotime-(Y)      YP[O.sub.4]
  Aegirine          NaFe[Si.sub.2][O.sub.6]
  Albite            NaAl[Si.sub.3][O.sub.8]
  Astrophyllite     (K,Na)[.sub.3](Fe,Mn)[.sub.7][Ti.sub.2][Si.sub.8]
  Baotite           [Ba.sub.4][Ti.sub.4](Ti,Nb,Fe)[.sub.4]([Si.sub.4]
  Eudidymite (?)    [Na.sub.2][Be.sub.2][Si.sub.6][O.sub.15].[H.sub.2]O
  Genthelvite       (Zn,Fe,Mn)[.sub.4][Be.sub.3](Si[O.sub.4])[.sub.3]S
  Microcline        Kal[Si.sub.3][O.sub.8]
  Quartz            Si[O.sub.2]
  Riebeckite        [Na.sub.2]([Fe.sup.2+],Mg)[.sub.3][Fe.sub.2.sup.3+]
  Thorite           ThSi[O.sub.4]
  Titanite          CaTiSi[O.sub.5]
  Zircon (?)        ZrSi[O.sub.4]


We thank Dudley Blauwet, Andreas Weerth, and Tom Moore for additional information on this locality.


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DIPIETRO, J. A., POGUE, K. R., HUSSAIN, A, and AHMAD, I. (1999) Geologic map of the Indus syntaxis and surrounding area, northwest Himalaya, Pakistan. In Macfarlane, A., Sorkhabi, R. B., and Quade, J., eds., Himalaya and Tibet, Mountain Roots to Mountain Tops, GSA Special Paper 328, 159-178.

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POGUE, K. R., HYLLAND, M. D., YEATS, R. S., KHATTAK, W. U., AND HUSSAIN, A. (1999) Stratigraphic and structural framework of the Himalayan foothills, northern Pakistan. In Macfarlane, A., Sorkhabi, R. B., and Quade, J., eds., Himalaya and Tibet, Mountain Roots to Mountain Tops, GSA Special Paper 328, 257-274.

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Herbert Obodda

Box 51

Short Hills NJ 07078

Peter Leavens

Department of Geology

University of Delaware

Newark DE 19716
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Author:Obodda, Herbert; Leavens, Peter
Publication:The Mineralogical Record
Date:May 1, 2004
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