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a rare manganese sulfate from the Kalahari Manganese Field
One of the more interesting but subtle surprises at the Tucson show was the presentation of a small pocket of crystals collected and sold initially as "green ettringite" for facet rough. Thanks to the work of the Robert Downs lab at University of Arizona, this has now been shown to be the rare species DESPUJOLSITE - although in crystals several orders of magnitude more important than any previously found. Both very different crystal habits are the same species. This is a world class find for the species, whether few of us have ever heard of it or not, and so i am happy to present it here. They make for stunning, unusual, competition-worthy thumbnails ; and in person look more like green brazilianite than anything else we have seen from the Kalahari. I did purchase the entire pocket, and about 3/4 of the better crystals are presented here. Whether more come out, time will tell. But for now, this seems to be it. I heard no rumours of other finds, and this was reported to have been hit last summer.
A sharp and totally gemmy transparent crystal. Note that these are spectrum sensitive and the photos show the piece under both halogen (moss green color) and under fluorescent (brighter apple-green color) lighting.
A small but sharp and utterly intensely colored crystal showing nice form. Note that these are spectrum sensitive and the photos show the piece under both halogen (moss green color) and under fluorescent (brighter apple-green color) lighting. (and again, small here is all relative - this is 1000 times better than any previously known!)
A rare matrix specimen, sadly one of only a few recovered when the miners scraped out this pocket. The elongated, very fine crystal atop is 1.5 cm long. It is fully terminated and displays well.
A remarkable flattenned crystal showing a pseudohexagonal form, unusual in such good presentation. The bottom is included with another mineral, possibly manganese.
Sharp single crystal, with great terminations at either end. (and again, small here is all relative - this is 1000 times better than any previously known!)
One of the largest crystals in the lot, with a huge presentation face and intense coloration. Terminated on about half the edges, contacted on the rest, it nevertheless displays well and is of museum caliber in terms of its importance.
A remarkable flattened crystal showing a pseudohexagonal form, and exquisite finely serrated edges. This piece is nice because it gives the illusion of being a matrix specimen due to inclusions (manganese?) at its base, forming a natural pedestal for the competition-quality crystal atop.
A slender but sharp crystal showing nice form. Note that these are spectrum sensitive and the photos show the piece under both halogen (moss green color) and under fluorescent (brighter apple-green color) lighting.
A small but very sharp, very gemmy crystal of good quality. (and again, small here is all relative - this is 1000 times better than any previously known!)
A sharp and totally gemmy transparent crystal. Although rough on the top edge, I think it is terminated. Note that these are spectrum sensitive and the photos show the piece under both halogen (moss green color) and under fluorescent (brighter apple-green color) lighting.
A remarkable flattenned crystal showing a pseudohexagonal form, and exquisite finely serrated edges. Sharp, competition-quality crystal among the best of this style here. Note that these are spectrum sensitive and the photos show the piece under both halogen (moss green color) and under fluorescent (brighter apple-green color) lighting.
A small but sharp crystal showing nice form (we already sold off lesser, broken crystals for research or to try gemcutting, so even the small ones here are cherrypicked)
A small but sharp crystal showing nice form (we already sold off lesser, broken crystals for research or to try gemcutting, so even the small ones here are cherrypicked)
A fat, 3-dimensional, intensely colored crystal showing superb form. Note that these are spectrum sensitive and the photos show the piece under both halogen (moss green color) and under fluorescent (brighter apple-green color) lighting.
A rare matrix specimen, sadly one of only a few recovered when the miners scraped out this pocket. Absolutely gemmy, transparent crystals to 6mm decorate this pedestal of manganese gangue matrix. In person, its very sharp and pretty. The crystals here are among the most transparent in the lot.
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