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What's New in Minerals: Denver show 2001.

[September 10-17]

Wendell Wilson and had been booked to fly the United Airlines shuttle to Denver on the afternoon of Tuesday, September 11, 2001. As it turned out, the morning of that day will always bear resonances unrelated to the Denver mineral show. I hope that readers will understand if this report comes out sounding less chipper than usual; a muted tone also characterized the atmosphere of the show, as specimen-shoppers were understandably unable fully to enjoy minerals in the usual way. Every TV screen in every hotel room showed, in endless replay, the horrifying destruction of the World Trade Center in New York.

With the nation's airlines still grounded on Thursday, we finally embarked somberly on the 13-hour drive to Denver from Tucson. The personal irony is that I had been looking forward to the easy one-hour-plus flight, instead of the seven-hour flight from eastern Connecticut (with at least one plane change) that I'd always taken to Denver before. On those previous flights, as the plane passed south of Manhattan, I would always make it a point to look out the window and down at the glistening, crystal-like shapes of the World Trade Center's twin towers, spectacular far below in the dawn, even while the rest of the city lay submerged in haze. Now, instead, we took in the desert vistas and the majestic Rocky Mountain scenery, from southern Arizona up through New Mexico and Colorado: beauty that no mere terrorist can ever hope to deface.

Mindful of the disasters in New York and Washington, the Show itself did its part to join in supportive solidarity. The Board and the Trustees of the Denver Mineral Council and the committee in charge of the Denver Gem and Mineral Show voted unanimously to donate the net proceeds from admissions in 2001 to a victims' relief fund for the families of those who died. Yes, it was a "muted" show; many regular show-goers chose to stay home or couldn't make it because of canceled flights, and some dealers lost money because of reduced customer traffic. But, in spite of everything, the Show did go on, and with lots of interesting minerals too. So, minerals being our business, let's get down to it.

Lanny Ream (P.O. Box 2043, Coeur d'Alene, ID 83816) has continued the good work he was beginning just before this year's Tucson Show, extracting large numbers of very large and fine heulandite specimens from the prospect he calls the "Rat's Nest claim," near Challis, Custer County, Idaho. About 100 top specimens have appeared so far, and Lanny had most of them in his room in the Holiday Inn. On a pale gray, altered andesite, the heulandite forms as typically fan-shaped crystal aggregates to 4 or 5 cm across their tops, and these occur on thick cavity-lining beds of pure white hair-like mordenite crystals. The luster of the heulandite is very bright, and the color is a gorgeous pale peach-pink. Some miniatures consist of two or three intergrown heulandite fans without matrix, but the really dramatic ones are the matrix pieces, which reach up to a foot across. Other specimens show mordenite alone, with the blankets of filiform crystals rising up in places to form white "puffball" mounds to 5 cm across. Glisteni ng, freestanding mordenite crystals comprise the puffballs--but no petting! These are not the flexible Indian okenite puffballs that they resemble.

In the same wild region of central Idaho, at a place called Antelope Flats, Lanny has dug some very large specimens of a new and unique phenomenon: milky quartz pseudomorphs after apophyllite. Individual pseudomorphed crystals can reach 4 x 7 cm, while still displaying their forms sharply enough to recall instantly the Indian apophyllite crystals of the same habit: thick tetragonal prisms with large pyramid faces and no pinacoids. The quartz is grayish white, forming thick casts with bumpy surfaces covering a thin (fluorescent) calcite layer, under which lies a boxwork of quartz where the big apophyllite crystals used to be. These specimens are not beautiful, but crystal clusters can reach 45 cm across. All came, Lanny says, from a single huge cavity in a surface exposure.

The long-famous Elmwood lead-zinc mines near Carthage, Smith County, Tennessee have for decades turned out stunningly beautiful specimens of calcite, fluorite and sphalerite in prodigious abundance. At the Main Show, fully a third of all the specimens in the large booth of Bryan Lees' Collector's Edge Minerals were Elmwood pieces from a recently acquired accumulation built over 20 years during the mine's heyday. The specimens are of such uniformly high quality that they obviously must have been carefully cherry-picked from vast numbers of specimens by someone with close access to the mine and its output. Specimen sizes range from thumbnails to "museum" behemoths. As this material is generally familiar, it need not be over-described here--but picture lustrous, gemmy, perfectly formed pale yellow to deep orange calcite crystals to 15 cm; pale to deep purple fluorite cubes (some of the darker ones having scalloped surfaces) in all sizes; brilliant reddish brown sphalerite crystal-hodgepodges on plates of cherty matrix; 10-cm spheres of pale yellow barite crystals; oh yes, and a few fine galena specimens too. This was surely the best Elmwood assemblage gathered in one place in a long time, and prices were reasonable, especially considering the sheer-beauty factor. Several other dealers around the show had Elmwood spreads just about matching that of Collector's Edge for quality, if not in numbers of specimens. If you want a good Elmwood something-or-other, or even a suite, now's the time.

A remarkable 100 or so old-time, gemmy green "hiddenite" spodumene crystals from the classic locality on the Warren Farm, Alexander County, North Carolina were on view in the Holiday Inn room of Terry and Jean Ledford of Mountain Gems & Minerals (P.O. Box 239, Little Switzerland, NC 28749). These loose single crystals were collected who-knows-how-long ago, reportedly from a single pocket, and had been unavailable until the Ledfords acquired the lot. The color is a rich medium green, and gemminess is total (unless you subtract points for the inevitable small etching channels). The crystals are sharp, with slightly scalloped, sloping terminal faces, some of these with the odd little curl on top that we've seen in pictures (such as the one in Bancroft's Gem and Crystal Treasures, in the Hiddenite, North Carolina chapter). All of the hiddenite crystals are thin, and have lengths ranging from 2 to 5 cm, and prices ranging from $400 for a small thumbnail to $5000 for the single 5 cm-long specimen. I hardly need to add that these are major classics, close to impossible (until now) to find on the market. A reminder is sometimes necessary that, although gemological varieties like hiddenite are not as well-defined as actual species, true hiddenite (like emerald) must draw some of its color from chromium. Much green spodumene from Brazil has incorrectly been labeled "hiddenite" though lacking the chromium chromophor.

At the Tyson's Minerals stand at the Main Show, Rod Tyson was proudly showing a world's-best-for-species item collected this past summer at the Big Fish/Rapid Creek area in the far northern Yukon (relevant Special Issue: Yukon Phosphates, vol. 23, no. 4). The species is whitlockite, best known heretofore in microcrystals from the Palermo #1 mine, New Hampshire, and other old phosphate pegmatite occurrences. No micromounts, these new ones, but rather lustrous gray-white to palest green, translucent tabular crystals from 5 mm to 2 cm, growing individually and as tight clusters on dark blue matrix of massive rare phosphates (gormanite, kulanite, arrojadite, etc.). A superlative thumbnail with a 2.2-cm whitlockite crystal standing up edgewise on matrix was priced at $500, but other thumbnails, still impressive, ran down to $50. And for $900 there is one 5 x 6-cm piece of matrix covered with jumbled white whitlockite crystals all around 1 cm.

A nice Mexican entry in the what's-new derby is some brand-new, beautiful "optical" calcite from near Rodeo, Durango, Mexico. Matthias Jurgeit of Lampertheim, Germany has been digging the specimens from an unnamed prospect, as have also some local farmers, so that the excavation is now about 4 meters wide and 7 meters deep. The calcite vein is hosted by a rhyolitic tuff, and it contains vugs up to 60 cm wide. Since this past January, between 250 and 300 specimens have been produced, of which about 30 are butterfly twins; the rest are very attractive sprays of steep scalenohedral crystals, and rounded clusters of flattened rhombohedrons. Specimen sizes range from 4 cm up to around 15 cm. The luster is silky, and the crystals are almost colorless to faintly gray, and completely transparent. Matthias Jurgeit partners up with Ed Huskinson in a dealership called Luadra Minerals (4804 Steinke Dr., Kingman, AZ 86401), whither you may apply for specimens (since more will almost surely come out, and the Mexican prospe ctors, Ed says, are learning the skills necessary for damage-free collecting).

In the same room at the Holiday Inn, Matthias Jurgeit was showing some nice specimens from Cerro del Mercado, Durango, Mexico, the source of gemmy yellow fluorapatite crystals. Since 1828 the hematite-infused breccia of Cerro del Mercado has been mined for iron; for decades during the 20th century the apatite crystals were plentiful on the specimen market, becoming much less plentiful after the mine closed in 1975. But commercial mining began in another part of the orebody in 1993, and now the pretty crystals are tricking out again. In the Luadra room in Denver, about a dozen loose gemmy crystals to 3 cm and a couple of flats of miniature-sized matrix specimens with apatite crystals to 2 cm were available. The hexagonal-prismatic crystals seem almost never to be doubly terminated, but sharp pyramidal single terminations are common enough, and the crystals are often transparent enough so that one sees the rough reddish matrix straight through all that rich orange-yellow. A few of the single crystals have waxy looking bits of grayish white hyalite opal adhering to their sides.

Andy Seibel (P.O. Box 2091, Tehachapi, CA 93581) has acquired about 20 very nice specimens of the boleite that Ed Swoboda mined in the 1970's from the renowned Amelia mine at Boleo, Baja California, Mexico. All specimens consist of brownish/reddish/greenish, amorphous-looking stabilized matrix in which are embedded the sharp, deep blue boleite cubes, all around 1.5 cm on edge. Specimen sizes range from 4 x 4 to 6 x 8 cm. I saw no stepped edge-ridges that might betray possible overgrowths of pseudoboleite on any of the blue cubes: they are bright, sharp, and clean crystals, and, of course, utterly distinctive for this classic occurrence.

A shipment of very fine Japan-twinned quartz from Peru only got in to Denver on Saturday, and spies alerted me in time so that I could see the specimens and get the scoop from their owner, Giovanni Russo of Mineral Center (Gran Mercado Inca, Av. La marina 884, Tiendas 13-14 Pueblo libre, Lima, Peru). Last January, about 150 of these quartz specimens, in sizes from small miniatures up to cabinet pieces, were found in a vein in the polymetallic ore deposits of the Mina Flor del Peru #2, near Pampa Blanca, Castrovirreyna province. A few shows ago I reported on a similar hoard of Japan-twinned quartz whose locality was then given simply as "Pampa Blanca"; it turns out that this is the name only of the nearby town, and the mine from which the earlier lot came is the Flor del Peru #1, #2 or #3, all three mines being within a few miles of the town. The quartz crystals are mostly frosty (a very few are glassy), but the twinning form is sharp, with varying re-entrant angles, and the twins reach an amazing 12 cm across . Most of the large clusters, to 25 x 25 cm, consist of conventionally prismatic quartz crystals with just one or two Japan-law twins sitting prominently in their midst, but there are also a few clusters of all Japan-law twins, including one fascinating 15 x 22-cm group of maybe 100 twins, from 1 to 4 cm, all flaring irregularly from matrix, like butterflies on a log preparing for takeoff. There is little or no matrix on the majority of the pieces, and no hint of any associated species.

A pocket found very recently in the Viboras vein of the Machacamarca mine near Cotavi, Potosi, Bolivia has given up a number of unusual bournonite crystals measuring individually from 3 x 3 cm to a giant 6 x 6 cm! The crystals are tabular, apparently twinned "cogwheel" plates with a dull to metallic luster and/or an earthy black coating on the big plate faces and a complexity of small, much more lustrous, steel-gray faces around the edges--big metallic gray "ears" unlike any bournonite crystals generally familiar to collectors. Cement-gray shards of rock and subhedral brown rhombohedra of siderite cling here and there to the surfaces. Rob Lavinsky of The Arkenstone had about 20 miniature to small cabinet-sized specimens; Excalibur Minerals had about ten more, and there were isolated examples in other hotel rooms.

Brad and Star Van Scriver of Heliodor were offering--besides the show's best hoard of almost surrealistically fine new Moroccan vanadinite--about 15 thumbnails and small miniatures of a very appealing blue fluorapatite just found in a pegmatite prospect somewhere in the state of Paraiba, Brazil. Sharp, very lustrous, deep blue to mottled blue-white, translucent to gemmy fluorapatite crystals reach 1.5 cm; they are fat hexagonal prisms with pyramid and pinacoid faces, and they rest on velvety beds of fine-grained muscovite with a few incomplete gray-green elbaite crystals lurking inside the mica. Specimens with one or two bright blue apatite "barrels" lightly attached to the silvery gray matrix score an aesthetic Ten.

The sharp loose prisms of xenotime from Bahia, Brazil have been known for some time, but three huge crystals shown in the hotel ballroom by Doug Wallace may well be the world's best xenotime specimens (Marty Zinn bought the very best one early on in the show). Doug, of Mineral Search, Inc. (11882 Greenville Ave., Suite 123, Dallas, TX 75243) gave the locality name as "Ibiajara"--fairly close, by Brazilian locality-name standards, to what has been given in the past. The xenotime crystals are a deep yellowish brown, slightly rough-surfaced tetragonal prisms ending smartly either in four equal pyramid faces or in two, for a wedge-shaped termination; the Big Three are 4, 5 and 5 em high. Flashing yellow-brown highlights play just under the bright glassy surface. Doug got the three giants, and eight thumbnail crystals too, from the Jerry Manning (Texas) collection. Xenotime is a phosphate of yttrium and the rare-earth metals, and analyses of these specimens show a very high 8% dysprosium content.

Also from Brazil, Luis Menezes (R. Esmeralda, 534, Belo Horizonte--30410-080--Brazil) had his usual bunch of small surprises. For one, he had much better thumbnails than previously of beryllonite from the Telirio mine, Linopolis, Minas Gerais (already familiar as the source of the fine, sharp brazilianite crystals of late). The beryllonite comes as sharp cyclic twins, milky white to translucent to transparent and colorless, reaching 1 cm, in about ten thumbnail clusters without matrix (average price $125). And there is one astonishing, lustrous, transparent-colorless fishtail twin of beryllonite measuring 6 x 7 cm (unfortunately broken along the twinning plane, but soon to be repaired).

From another mysterious small hole near Linopolis came, last June, about 20 matrix specimens and 100 loose groups of medium-green gormanite in spheres of radiating acicular crystals, on sharp blades of "cleavelandite" albite. The spheres reach 3 cm across, and are earthy green in surface appearance. The best specimen Luis had is a 6 x 6-cm albite matrix with two intergrown 3.5-cm gormanite balls.

Luis' third noteworthy offering consisted of several flats of loose thumbnail and small miniature-sized crystals of andalusite from the Jenipapo mine, Itinga, Minas Gerais. Not pretty, but quite good for the species, the andalusite crystals are an opaque to translucent pinkish brown; the wedge-terminated prisms get up to 4 x 4 x 5 cm, with traces of the massive quartz in which they are found embedded. The quartz, in turn, forms veins in a schist surrounding a pegmatite. Luis has hopes for more specimens in the future as exploration continues.

A geologist friend of Dave Bunk has brought up a substantial consignment of specimens of very fine inyoite with meyerhofferite from an evaporite deposit at Nacimiento Sijes, Satta province, Argentina. About 50 surprisingly attractive miniature and cabinet-sized specimens were to be found in Dave's room in the Holiday Inn. The inyoite forms colorless, transparent rhombohedrons to 8 cm, partly tinted pale brown by included clay. Some of the inyoite in the clusters of crystals is still entirely "clean," i.e. not yet dehydrated or altered, while in other specimens the inyoite crystals show partial fillings of needle crystals of white meyerhofferite. Specimens range from miniatures for as little as $10 to big 22-cm clusters for $1000.

Also from Argentina (an "undisclosed" locality some 400 km southwest of Buenos Aires) have come two of the oddest magnetite (?) specimens anyone has ever seen, both in the keeping of John Attard (www.attminerals.com). One specimen, measuring 3 x 3 x 6 cm, is a prism of four equal sides, the sides bordered by solid black pillars, but deeply cavernous on the faces, with parallel-growth chevrons pointing upwards; at the top, four ridges slope up from the corners like flying buttresses to form a "roof." The other specimen, measuring 1.5 x 1.5 x 11 cm, is a long tower of the same stacked-chevron development up the shaft, and a small wedge termination. Surfaces on both specimens are sandpaper-rough, and the overall color is black, with some red staining. John was told that the species is either hematite or hematite pseudomorphous after magnetite ("martite"), although somehow they look more like magnetite, especially as there are simple black magnetite octahedrons around one end of each specimen.

Europe pretty much struck out this time in the what s-new batters' box, but this seems a good place to salute Wayne an Dona Leicht of Kristalle for their usual juicy selections (as also at Springfield and Tucson each year) of old European classics. Chief among these at the Main Show in Denver were six outstanding old Kongsberg, Norway wire silver specimens, from a couple o loose 3 x 4-cm nests of bright, thin wires to a majestic 17-cm piece with silver wires of varying thicknesses "nesting" all over a cluster of white rhombohedral calcite crystals to 2 cm.

Brilliant black plates of hematite with epitaxial rutile from Cavradischlucht, Graubunden, Switzerland are hardly "new" either, but Marshall Kovall of Silver Scepter Minerals (P.O. Box 3025, Kirkland, WA 98083) had about 15 terrific miniatures of the material, dug recently by some heroic Strahler. The hematite plates are up to 3.5 cm wide, and they sit up singly, edgewise, or else form subparallel, offset clusters ("iron roses") on gneiss matrix with albite crystals to 1 cm. There is very little damage on any of these specimens, and they're bargains at $75-$350.

At Gilbert Gauthier's stand at the Main Show I talked with Dr. Georg Gebhard (D-5 1545 Waldbrol-Grossenseifen, Germany) about the currently very hot localities for aquamarine, tourmaline-group species, and jeremejevite in the Erongo Mountains, Namibia. Especially interesting among the specimens being offered by Gebhard were the combinations of gemmy aquamarine crystals with deep bluish black foitite, a high-iron member of the tourmaline group. Foitite crystals from Erongo are highly lustrous, with rich blue internal reflections sometimes discernible in backlit portions of thin crystals; most of the foitite crystals are thinprismatic to acicular, occurring in parallel bundles and jackstraw clusters, and a few thicker crystals show etching down to a ridge of trigonal (Mercedes-Benz) shape on one end. There may be one or two rarer tourmaline-group species present, and whether or not the beautiful, thick, lustrous black "schorl" crystals from this locality are also foitite is a matter of some debate. The crystal s come in all sizes up to about 10 cm, and the ones with aquamarine, or on matrix with little green fluorite cubes, are very striking. Rocko and Mandy Rosenblatt of Rocko Minerals (Box 3A, Route 3, Margaret-ville, NY 12455) were meanwhile offering, in the Holiday Inn, their best-yet specimens of Erongo schorl, in flashing black clusters of near-perfect 8-cm crystals.

Ongoing digging in the Erongo wastes has recently also turned up a pocket of jeremejevite crystals from 1.5 to 4 cm long, all specimens being thin, loose singles. They vary from almost colorless to a pale greenish blue to a most desirable (but unterminated) deep blue; from the last type some nice faceted gems have already been cut. Gebhard had five loose gemmy jeremejevite crystals, and the Leichts had five more.

Meanwhile, old Namibia specialists Christian and Petra Gornick of Fine Minerals Worldwide (Reutergartenweg 20, D-31319 Sehnde (Hover), Germany) came through at the Main Show with some really beautiful hematoid quartz specimens from the "Oranje River," a vast collecting area straddling the border between Namibia and South Africa (though the better specimens are found n the Namibian side). I have noted these before, but there were no thumbnail-sized specimens before, let alone specimens as nice as the Gornicks' fat, doubly terminated 2-cm prisms with bright brick-red zones sharply bounded by colorless zones. The miniature-sized quartz specimens show prisms zoned in many colors from yellow to pink to brick-red to amethyst, from inclusions of hematite, lepidocrocite, and an unknown species. A big dig for further specimens is now on, but the best thumbnails here were already good deals at around $20.

You might recall that at the end of his recent Ste.-Marie-aux-Mines show report, Bill Larson described his meeting with a French dealer who was selling off some fine old classics, mostly from Madagascar, from the collection of Jean Jacques Francis Behier (1903-1963), who once worked as a mineralogist for the Geological Survey of Madagascar. Well, apparently the dealer didn't sell everything off in France, for here he was in a Holiday Inn room, making his maiden visit to the Denver Show with a still-considerable lot of material from the Behier collection. He is Alain Martaud of Mineraux de Collection (33 Rue Compans, 75019 Paris, France), and he was having a fine time showing off his good stuff to appreciative inquirers. Included were Madagascar rare-earth classics like sharp betafite crystals to 4 cm; well-composed earthy brown sprays of 2-cm euxenite crystals; swarms of loose 1 and 2-cm cubes of lustrous black thorianite; and allanite crystal groups from Madagascar and from Alto Ligonha, Mozambique. In addit ion there were Scandinavian classics like loose, sharp 2-cm pyritohedrons of cobaltite and sharp, lustrous pseudo-octahedrons of glaucodot from Sweden; well crystallized leucophanite, columbite and thortveitite from Norway; and richly brownish red, euhedral crystals of eudialyte to 2 cm in complex ultra-alkaline matrix, not from the Kola Peninsula, Russia, but from 19th-century localities in Greenland. European classics from the same collection included Cumbria, England fluorite and calcite; fine "toenail" crystals of azurite from Chessy, France; "heliodor" beryl from the island of Elba, Italy; and much else. There was also a Tsumeb array, with fine small specimens of mimetite, smithsonite and hydrocerussite after cerussite. Educational classics, a friendly reception, and generally very reasonable prices, all made this (for me, at least) perhaps the most enjoyable hotel room visit at the Denver Show this year.

Yet another educational-room experience, and another dealership new to the U.S. show scene, was Igor Mikhailov's "Axinite-PM" Ltd. (22 A Rogova str., Moscow, Russia 123479). Although there were indeed many fine Russian minerals here, especially from Dal'negorsk, the really new, unfamiliar items were from the ex-Soviet republics of Kazakhstan and Uzbekistan. The copper mines of Dzhezkazgan, Kazakhstan were well represented by many excellent specimens of chalcocite, betekhtinite and djurleite, from thumbnail to 5-cm sizes, in lustrous metallic black crystal groups, the djurleite distinguishable from the chalcocite by its prismatic crystals, splintery aspect, and blue-purple iridescence. Also there were, predictably, some very fine Dzhezkazgan bornite crystals on drusy quartz matrix. Much rarer from Dzhezkazgan are the floater single crystals and groups of cuprite that show reports have noted before: Mikhailov had dozens of these, with fairly lustrous and sharp (though slightly corroded) deep red cuprite octahed rons in 1.5 or 2-cm singles and in groups to 3 cm.

But this reporter had never heard of an open-pit copper mine called the Itauz mine, which lies, Mikhailov says, about 40 km from Dzhezkazgan, and which supplies some very fine specimens of cuprite and native copper. Of the copper there were 200 or so thumbnails and miniatures in the room: fuzzy arborescent groups and sharp stacks of spinel-twinned crystals individually to 1 cm. The luster is not bright, but the price is still right--around $40 for an excellent thumbnail. Also from the Itauz mine comes a very dark cuprite, in lustrous, blackish red, distorted octahedrons to 5 mm composing loose groups and scattered over platy masses of subhedral copper crystals. Next, from the Karzemkkul deposit, Kustany Oblast, northern Kazakhstan, the dealership had about 30 miniatures of massive black magnetite solidly covered on open-seam surfaces by brilliant black, sharp magnetite octahedrons to 1 cm, further bedecked with grayish green, isolated, sharp books of clinochlore to 1.5 cm. These specimens were mined two years ago. From Sortuz, Kazakhstan, came three 4-cm matrix pieces of greenish (pyromorphite-infused) iron gossan with open seams lined by vividly red-orange, equant wulfenite crystals to 5 mm. But the truly weird wulfenite specimens are those from Sedjak, Uzbekistan: bright red-orange loose crystals to 2 cm, so thick along the c-axis as to appear almost equant. This room in general taught you what "exotica" can mean--familiar species in unfamiliar manif estations from deepest Central Asia, is what it can mean.

Concerning the minerals of the Deccan basalt flows of India, I should mention that longtime Indian dealer K.C. Pandey (of Superb Minerals India Pvt. Ltd.) is now publicizing the new museum of Indian minerals he has just opened in Nasik; the museum is called "Gargoti," and doubtless contains specimens just as beautiful as those which filled his room, as usual, in the Holiday Inn. I should also mention that two of the most spectacular of the display cases at the Main Show were filled with Indian specimens, many of them supplied by Pandey, from the collection of Steve and Clara Smale. But what I will really mention is that Berthold Ottens of Ottens Mineralien (Klingenbrunn-Bahnhof 24, D-94518 Spiegelau, Germany) brought to the Main Show a few small specimens of two little-known rarities from the Deccan region: pentagonite and julgoldite. Pentagonite is a dimorph of cavansite, has the same incandescent blue color, and occurs in the Wagholi quarry, Poona (and in smaller quarries in the vicinity), in association wi th the familiar cavansite. The difference is that pentagonite crystals are acicular, reach 1 cm long, and occur in needly sprays very unlike the balls or parallel-growth sheaves of cavansite. A few specimens have just recently been found which are better than the (mostly micro-sized) pentagonite specimens known previously; the brilliant blue sprays rest on pocket linings of white to colorless-transparent heulandite crystals, with a little stilbite. These sprays range from 1.5 to 2.5 cm across. Ottens had ten matrix specimens from 4 to 10 cm. Julgoldite, on the other hand, is a complex silicate belonging to the pumpellyite group. It is dull black, and occurs as microcrystals coating white mordenite needles; these specimens make you think that a white zeolite has been attacked by a mold, i.e. they are not pretty. But the few thumbnail specimens which Ottens had, found two years ago in Jalgaon, are probably the best specimens possible, at least in India, of this very rare species.

Web shoppers and earlier show-report readers may already know of the tremendous specimens of the rare-earth silicate chevkinite(Ce) lately uncovered in the Nanga Parbat area of Pakistan. I saw fewer of these in Denver than I had expected to, but three crystal groups held by Andreas Weerth might attain the size record: the brownish black chevkinite crystals are heavy blades to 6 cm across, most of them dull-lustered but a few very glossy. Also Andreas had what may be the world's biggest crystal of the hexagonal cancrinite-group species afghanite: a tapered medium-blue, fairly sharp prism 4.5 cm long, embedded in white marble, from the lazurite locality in the Kokcha Valley, Badakhshan, Afghanistan. Herb Obodda, Dudley Blauwet and a few other dealers had fairly good supplies of the pretty pink "hackmanite" (the widely used name for this variety of sodalite) from the Kokcha Valley. The embedded "hackmanite" crystals, though edge-rounded, are still fairly sharp at their best, and reach 5 cm across. They exhibit a n interesting color change, from pale lilac/magenta in artificial light to a deep purple/magenta in sunlight. This is not a passive, alexandrite-like color change but a genuine photo-sensitive darkening which takes about 10 seconds once a specimen is brought Out into direct sunlight. And the phenomenon is reversible, the specimens turning pale again after being left in the dark for a few hours. They are also intensely fluorescent, glowing orange in longwave ultraviolet light and pale blue in shortwave, and phosphorescing for an incredibly long time after the light is turned off. Further, Herb Obodda's hackmanite crystals are embedded, not in the white marble we'd expect, but in yellowish brownish white groundmasses of an amphibole called winchite, with large, tabular glassy crystals of the winchite surrounding the hackmanite crystals. Peculiar stuff indeed.

China has produced beautiful specimens of at least three as-yet undetermined copper species occurring in big, heavy blocks of dense red hematite ore (it looks like hematite, though cuprite would make more sense). These are so new that Debbie Meng's two specimens are all that there were in Denver (Debbie has more, but they're still back ia China). Given that these are green secondary copper minerals in ore matrix, it is surprising that they come from the same locality that has lately been producing the radically different-looking specimens of pink inesite, colorless apophyllite, and brown hubeite: the Daye mine in Hubei province. Debbie's larger piece is a 10 x 15-cm matrix with a deep cavity opened up on much of its surface, In the cavity, aurichalcite-like tufts of lustrous bluish green needle-crystals (brochantite?) vie for attention with sprays and sprinidings of a thin-prismatic, lustrous, blackish electric-green mineral (atacamite?), in crystals to perhaps 2 mm. The specimens remind me of the brochantite/cyanotrichite combinations from the old Grandview copper mine in the Grand Canyon (although these carried no atacamite). Under it all, as a seam lining, is a velvety black manganese or copper oxide. At any rate, these are dramatically beautiful specimens; if commercial quantities become available the specimens should become instant Chinese "classics."

Finally, shaft #3 of the Wuling antimony mine, Qingjiang, Wuling County, Jiangxi Province, China, has very lately yielded what are certainly some of the world's finest stibnite specimens. Collector's Edge Minerals acquired the lot, and I was able to see some of the top pieces during a visit, in July, to the Collector's Edge shop in Golden, Colorado; at the Denver Show, many of these specimens and hundreds of others were available from Collector's Edge in their booth at the Main Show and in their room at the Holiday Inn.

The stibnite crystals are a very clean metallic gray-black, lightly striated, and with a uniformly brilliant luster along the prism faces (most termination faces are matte-gray), and there is remarkably little damage on any of them. Most of the specimens are single loose crystals, but there are also dozens of crystal clusters in subparallel growth and irregular jumbles; many preserve small matrix base plates and/or have side-adhering shards of gray chert sparkling with microcrystals of quartz (there are no other associated species). The sheer size of the stibnite crystals is amazing. The biggest I saw in Golden is 40 cm long (and only about 1.5 cm wide and thick--with no repaired breaks!). Several other crystals attain lengths of around 35 cm, and one slightly flattened 1 x 2.5 x 35-cm floater is actually doubly terminated. A highly aesthetic 37-cm specimen has two thin, bright prisms, 23 and 26 cm, rising from a 4-cm piece of matrix held to the side by girderworks of smaller crystals, and then a terminated 8 -cm prism continuing due south from there. All crystal terminations are very simple: pairs of flat, faces forming simple low-angle wedges, only a few having one or two additional terminal faces beveling the chisel. These simple terminations are markedly different from the complex and highly lustrous terminations typical of old Japanese specimens and of stibnite crystals brought out during the last few years from the Xikuangshan antimony mine near Lengshuijiang, Hunan, China.

Two large stibnite pockets were encountered in the Wuling mine late in 2000. In late November the first pocket was hit in shaft #2, but blast damage and faulty recovery techniques destroyed most of the contents. In early December a second large pocket was hit in shaft #3, and this time the miners were counseled and coached in damage-avoidance by several Chinese mineral dealers who had had experience in collecting out crystal pockets at the Xikuangshan antimony mine; consequently the shaft #3 pocket at the Wuling mine yielded several hundred fine specimens, of which 25 or so are world-class. Although the mine has been ia operation for about 20 years, all stibaite crystals found before the discovery of these two pockets were processed as antimony ore--credit Civilization, therefore, with having taken one small step forward. Prices for these exceptional pieces at Denver were pretty civilized too: an abundance of fine large cabinet specimens of stibnite were available for $300 to $500. Four-figure prices were ask ed for some really large and spectacular clusters ia the glass cases, but excellent smaller specimens, with stibnite crystals to 8 cm long, could be had for under $100.

Space constraints forbid a detailed review of all the displays at the Main Show. It was heartening to see, however, that all of the cases were filled, some by local collectors coming to the last-minute rescue when some of the out-of-state collectors and museum curators who had planned to bring exhibits got caught in the nationwide grounding of all airlines. Crowds at the Main Show were thin by the standards of previous years, but some dealers still did reasonably well, and those buyers who did come were treated to some very beautiful sights.

About ten showcases of minerals were supplied by various private collectors, clubs and institutions, addressing the theme of the "minerals of the Pikes Peak batholith"; fine, often enormous specimens of that Colorado trademark, smoky quartz with green microcline ("amazonite"), were all over the hall. But top honors ia the Colorado minerals department must go to the big case full of miscellaneous Colorado specimens seW-collected between 1972 and 2001 by Dan and Dianne Kile. This case proved the Kiles to be Colorado field collectors without peer (at least without living peer ... the late Clarence Coil being another famous name in Colorado field collecting), and no slouches, either, at presenting specimens aesthetically for display. In a way almost moving, the case summarized a field-collecting career of the highest skill and devotion.

I've already mentioned the two breathtaking cases of Indian minerals put in by Steve and Clara Smale. Memorable also was a fine case on St. Andreasberg, Germany, with an ancient, amazing pyrargyrite specimen over a foot across, put ia by Herb Obodda. The Smithsonian's case of new acquisitions showed examples of familiar occurrences available at recent shows, in specimens of the highest caliber. (The Smithsonian's Paul Pohwat made it into town with their exhibit just under the wire--his comrades, scheduled on a slightly later flight, got stranded in Washington.)

But it was Irv Brown's case of 22 extremely fine cabinet specimens that was the standout for show-stopping minerals, Following Irv's personal philosophy, there were no labels here to detract from the aesthetic impact. His exhibit was aimed squarely at the cognoscenti, as if to say, "If you don't already know what these are, you don't know enough to fully appreciate them anyway." Picking highlights here is a futile exercise, since all specimens were world-class, but personally I favored the Siberian sperrylite; the Kongsberg silver; the Idaho pyromorphite; the Cosquez mine, Colombia specimen with a 2 x 3-cm deepest green emerald crystal on a bed of sharp gray calcite rhombs; and the stunning Tsumeb cuprian adamite (from the one best pocket), an insanely bright green 4 x 7-cm cluster topped by a perfect 4 x 4-cm fan of thick crystals.

So it was a good Denver Show after all, despite everything. Even if the world should be harrowed by war and uncertainty in the coming months, let's promise ourselves to prevail over the forces that would keep us from enjoying what we love in life. See you in Tucson!

[ERRATUM: The chevkinite-(Ce) specimen illustrated in the previous issue (p. 489, Fig. 3) was actually from Jordi Fabre, not Mountain Minerals International.]

Franklin Show 2001

Joe Polityka

[September 29-30]

After the events of September 11, 2001 at the World Trade Center in lower Manhattan (where my wife and I both work) I realized that after family and friends, health, country and the Almighty, one's hobby can provide comfort in times of stress and need. With that in mind I packed up my family and headed to the Franklin, New Jersey Show. Unfortunately, the day started off cold, damp and dreary; however, by noon the sun was Out and blue sky could be seen in all directions.

Lots of folks obviously felt the way I did; attendance was good and about 50 or so tailgaters were set up on the athletic field adjacent to the indoor show. Of course, many old friends were there and, despite the somber mood, minerals were traded, bought and sold with the same vigor as at previous shows. The 25 dealers set up inside the building had plenty to look at; as in previous years there were many one-of-a-kind specimens with something to please every collector.

One surprise tailgater was Terry Szenics (4 Manchester Drive, North Massapequa, New York 11758). Terry told me he was back in the US and in the mineral business. Terry had several items in the "What's New" department, including specimens of the new species lemanskiite (a copper arsenate) from Guanaco, Chile. The specimens consist of generous sky blue, pearly masses in a rock matrix, mostly in miniature to small cabinet sizes. His second new item is penfieldite (a lead oxychloride) from Sierra Gorda, Chile. The transparent to white, bipyramidal crystals reach about 5 mm in size and are associated with blue boleite microcrystals. These were popular items at the show but Terry assures me he still has a good supply of both minerals available.

Carter Rich had his usual well-rounded inventory of specimens. Carter also was disbursing several flats of classic botryoidal mimetite from the old San Pedro Corralitos locality, Chihuahua, Mexico. The specimens, from the original find of the 1960's, were stashed away in the Fred Croad collection until Carter recently liberated them. They are all miniatures and small cabinet-size pieces having that pleasing lemon-yellow color we are all familiar with.

Rocko Rosenblatt of Rocko's Minerals (Box 3A, Route 3, Margaretville, NY 12455) had vanadinite crystals to 2 cm from Mibladen, Morocco. Most specimens are in miniature to small cabinet sizes and are from the recent find. Some specimens are the familiar aggregates of crystals while others consist of crystals on a white, bladed barite matrix. Prices were very reasonable.

Rocko also had transparent jackstraw quartz groups, in all sizes, from Jinkouhe, Sichuan Province, China. The crystals reach about 5 cm, most of them also doubly terminated, and are reminiscent of the old Jeffrey quarry, Arkansas groups. Some crystals have inclusions of what appears to be graphite.

In the evening I attended a club-sponsored dinner-lecture. The speaker was Lance E. Kearns, Professor of Geology at James Madison University in Virginia. Lance spoke about the mineralogy of the Franklin marble, a rock formation close to the hearts of the collector of Franklin, New Jersey minerals.

Be sure to set aside a day to visit this show next year. And, don't forget, bring your duplicate minerals so you can set up at the outdoor show.
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Author:Moore, Thomas
Publication:The Mineralogical Record
Article Type:Column
Geographic Code:1USA
Date:Jan 1, 2002
Words:6764
Previous Article:Tucson Mineralogical Symposium: Minerals of Africa. (Abstracts of the 23rd Annual).
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