On eof the finer dioptase thumbnail specimens we have seen: A choice cluster of dazzling, deep green, and gemmy Dioptase crystals. This thumbnail is entirely Dioptase, with the largest, 1.5 cm crystal perched beautifully atop the cluster. The Dioptases have superb luster, and they burn with a deep green fire. The condition of the specimen is excellent. A terrific, and very hard to come by, Dioptase thumbnail of top quality, that is WAY beyond the norm, for the sophisticated collector.
This dramatic thumbnail crystal of dioptase is perched on a pedestal of massive dioptase, and is just a hair under an inch long, and doubly-terminated. It displays phenomenally! It is complete on the front, but contacted in back (or it would be much more expensive as well). But, it displays as if it were one of the finest dioptase single crystal thumbnails you could want.
Reneville, Pool Dept., Republic of Congo (Brazzaville)
Miniature, 3.8 x 2.0 x 1.7 cm
Exceptionally large and fine, this doubly terminated crystal of lustrous and translucent, rich emerald-green dioptase measures a remarkable 3.8 cm in length. Ex. Collection of Gene Meieran via exchange (and valued $2800).
Superb cluster of dazzling, deep green, gemmy Dioptase crystals. Save for a small amount of attached matrix, this miniature is 100% Dioptase. The crystals have superb luster, and they burn with a deep green fire. The largest crystal, which is 2.2 cm long, is perched atop the cluster beautifully. The condition of the specimen is excellent, with only one tiny, minor bit of edge wear - it is virtually pristine. A terrific, and very hard to come by, Dioptase miniature of top quality.
Classic Congolese Dioptase cluster featuring lustrous crystals and very distinctive dark to medium-green mottling. The largest Dioptase is an impressive 3.4 cm, and it is doubly-terminated. There are about a dozen crystals composing this rich cluster. Good aesthetics, and from a well-known and historic locality.
Glorious pair of superb Dioptase crystals on a layer of fluorescent Calcite. Each of the major Dioptases is over 1.6 cm, and the mirror-like luster and the gemmy green fire cannot be beat by those from other locales. They are so good, in fact, that in the pics it looks like the surfaces of the crystals are pitted, yet all you are doing is looking down into the crystals seeing the green fire beneath the glassy surface. A superb miniature.
Aesthetically emplaced a sugary, snow white calcite matrix are a few glassy and gemmy, rich emerald green crystals of dioptase, to 1.6 cm across. This is nearly a world class thumbnail save for the tiniest wilbers on the tips of the two largest crystals. Still, this is a significant and beautiful thumbnail of dioptase on calcite.
A large and stunning specimen of classic old Congo dioptase, in a specimen of rare size and caliber for the locality. Reneville is knock for large blocky crystals as you see here. They have not quite the luster of a Tsumeb dioptase (or the best Kaokoveld pieces), but have even deeper green color to them. This would represent a specimen of excellent quality, most likely from the late 1960s or early 1970s I am told.
A glowing, translucent crystal of really quite large size for the locality AND the species....when lit from behind, it is extremely beautiful in a glowing, softly colored way that Tsumeb dioptases, darker in color, are not. This piece is flattish on the backside, but just contacted and not damaged. It LOOKS like a Tsumeb dioptase at first glance, because of the size, but the color is lighter and the inner core more translucent than you'd expect from Tsumeb. But at first glance, it looks like a 5k Tsumeb toenail!
A killer toenail featuring a 2.25 x 1 x 1 cm dioptase crystal perched atop a natural pedestal. No damage, this is pristine! The aesthetics are incredible. Would trim slightly to a full thumbnail, as well...
A gorgeous miniature dioptase that doesn't break the bank: this specimen features a main crystal 1.7 cm long and 1 cm thick! It has TOP color, luster, and is just much better in person than it appears, as with all dioptase in photos.
This is a colorful cluster of nearly massive dioptase, with admixed cerussite as well. From it spike out gem, elongated dioptase crystals to 2.1 cm! This is one of the few matrix specimens of this crystal style recovered from the mine as yet and who can say whether more will come? This habit of elongated crystals, in such gemminess, is really quite new, and beautiful. The massive dioptase knoll on which the main crystal sits has some evident damage and bruises, to be sure, but the piece is priced accordingly; and the important crystal is not damaged, despite its freestanding nature. It is partially coated on the backside by quartz, which helped to protect it.
Deep green crystals , some doubly-terminated, here reach about 1.5 cm and are clustered richly on quartz matrix. This specimen is pristine , except only for a few tivial peripheral crystals to the left or bottom depending on how you display it. It looks good horizontal, and vertical both. The crystals are sharp and 3-dimensional and "pop" out at you - looking for all the world as if they were glued onto the quartz matrix, because they are so remarkably freestanding! A choice cherrypicked specimen. When shipped to us, it was a protected pocket, from which this was trimmed out carefully.
A beautiful specimen, really unique in aspect, featuring sharp, sword-like dioptase crystals to about 1.5 cm. They have intense color and great translucency (gemmy when backlit), just popping up out of sparkling, drusy quartz matrix. The combo is really quite unusual, and the stark contrast makes this among the most pretty, even if with smaller crystals, of the specimens from the find. A special miniature for the sophisticated collector, I think.
A sharp single crystal of rather large size, with perfect termination showing a steep point. The whole crystal is highly translucent and actually also "gemmy" in some areas; and it GLOWS when backlit. Complete all around, this is a large, dramatic, full thumbnail specimen or small miniature (toenail). IT IS A KILLER...MUCH BETTER IN PERSON THAN THE PICS CONVEY. The sheer size and perfection of this crystal would be remarkable from any locale.
This central crystal is 4.6 cm tall! I have seldom seen or heard of such a giant dioptase crystal from ANY locale. The thing is crazy big - you just keep looking to see that it surely must be a composite crystal but, it is not. It is a straight, honest to god, single large crystal. The big one is flanked by smaller crystals (mostly complete, though a few have edge contacting), all with electric green color, good luster, and a glowing translucency that will make this pocket famous, I predict. It is hard to photograph dioptase, and I assure you these are quite better in person, this in particular. Mounted on a base, and stood in a case, it makes a very imposing full miniature. If it were from Tsumeb, you could add a zero to the price, too; but Kaokoveld is contemporary and mined more cheaply, so even great specimens do not cost as much as they should based on historical precedent for this species. Price aside though, this IS a great piece, worthy of any major collection.
A radial spray of pristine, glowing green, elongated dioptase crystals runs across the top of this flowery specimen. The crystals have the gemminess and transparency of this relatively new mine, which will someday be famous I predict. There is some damage to the massive dioptase knoll on which the radiating vertical crystals sit, but this is "matrix" anyhow and does not bother me visually. The brown, vitreous cerussite crystal in the middle is a nice accent. And, for the quality, they are in some ways even better than Tsumeb yet at a much lower price point for a great specimen (for size of crystal but also gemminess and translucency, surely). If from Tsumeb, you really could add a zero to the price these days.
Reneville, Brazzaville Department, Republic of Congo
Thumbnail, 2.9 x 2 x 1.2 cm
Exceptional, 2.9 cm doubly-terminated Dioptase from an older, classic locality. The luster is excellent, and the color a deep, beautiful green. One termination is partially contacted, but to find a DT Dioptase of this size so complete, and aesthetic, is unusual. This is a dominating, HUGE single crystal and makes for a full-sized thumbnail of some impact. It is a very fat, robust crystal that LOOKS like Tsumeb material (which would be thrice the price).
An extremely rare dioptase from the RAY MINE. Most people who see Arizona dioptase only see it from Morenci - this one was a big surprise to me and I doubted it until it was verified by an Arizona collector expert. The matrix is lighter weight than Morenci material, and the chrysocolla association is also distinct here. The dioptase here, though small in crystal size, has an incredible bright intensity and the crystals sparkle like sugar! It is a very beautiful, and rare, large specimen
Tantara Mine, Shinkolobwe, Katanga, Dem. Republic of Congo
Small Cabinet, 8.9 x 5.9 x 5.7 cm
Shattuckite is a rare mineral that seldom crystallizes. Here, it has formed large fat crystals as a replacement of a previous generation of dioptase, resulting in a pseudomorph, or replacement, after that original mineral that faithfully preserves the crystal shape of the first species. This large, display-sized specimen has dozens of sharp crystals in excess of 1 cm, in 3-dimensional clusters on matrix. Remnant dioptase is still present in some places. From 2010-2011 finds. This is one of only a small handful of specimens I have seen that even remotely approach this level of quality.
Toenail – A “gut feeling” but often overlaps between a large thumbnail and a small miniature
Miniature – Maximum 5.0 cm
Small Cabinet – Maximum 9.4 cm
Cabinet – Maximum 18.0 cm
Large Cabinet – Over 18.0 cm
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