A super esthetic old Bolivian Cassiterite. Mostly all Cassiterite crystals with just minimal matrix and a few small Quartz crystals, in exceptional condition. The luster is glass-like and the crystals are fully translucent to transparent. The photos here are not backlit but with rear lighting the crystals glow a bright yellow-green to orange. The largest crystal is 4.2 CM across, which is huge for the locale, very few came close to that size and almost never with this fine form and luster. In excellent condition as seen, there are minor small edge rubs to mention but no damage. This from the Les Hitchings collection which he obtained in 1985, the era of the top finds at this amazing locality. Cassiterite of this quality has not been seen since then. This piece does look a lot like a fine Chinese Amo Mine Cassiterite in form but the larger size of the crystals and the internal color are distinctly different.
Exceptionally well-crystalized Ludlamite on a matrix of Siderite and Pyrite. The Ludlamite is in both prismatic crystals and in spherical rosette form balls. The largest ball is a textbook perfect crystal cluster perched at the top of the specimen. No damage and with bright luster, vivid color and excellent esthetics. From the recent find at Huanuni, (Bolivia), these have been big news in the mineral world as they have outstanding quality and form.
Sulphur - large hoppered crystals
El Desierto Mine, San Pablo de Napa, Daniel Campos Province
6.4 x 3.2 x 2.4 CM (cabinet)
New Year 22
Very pure Sulphur in textbook perfect crystals showing aligned prism forms and hoppered faces. Excellent bright yellow color and in undamaged condition, a modern classic. The El Desierto Mine is a rather small operation located on the flanks of a volcano at very high elevation. It has not been worked for a few years and when we visited the locality some time ago it was really inhospitable to say the least. However the best Sulphur specimens in recent decades have come from here. Better pieces like this have vivid canary yellow color, very bright luster and are rather transparent. The color is much brighter than most specimens of the other classic localities (Sicily and Russia) and there is no hint of Petroleum inclusions that are common elsewhere. These large crystals show very clear epitaxial stacking and exceed 5 CM. Choice for the locale and for the specie. Far better than the usual quality from this unusual place.
A complete floater, crystallized on all sides with slender blade-like crystals of Frankeite radiating in clusters and ball-like aggregates. An incredibly rare mineral, all the best specimens known came from just a few small finds in Bolivia, this is a superb example from what may be the best of those discoveries about 35 years ago. Not long ago Frankeite was often called the rarest Sulfosalt in the world. That may have been true then but today that statement is not true though it is still very super rare. The well-formed balls and clusters are distinctive for this special find at the San Jose Mine. In excellent condition, this displays well from any angle. Ex Dr. Eugene Sensei Collection. As far as we know there have been no more found since about 2005.
Stannite is somewhat rare Sulfide that is not usually attractive unless it has some contrast with its matrix or a very good form. This specimen has a bright sparkling Pyrite matrix with excellent luster that hosts some Stannites in well-formed, complex twinned crystals. The largest Stannite is 1.3 CM across. There is a little Zinkenite in the mix as small but fat needle-like crystals that need a close examination to find. This is from the San Jose Mine which has produced many incredible rare Sulfides and Sulfosalt specimens over the years. This piece is roughly 20 years old from the golden age of this important locale. There is no sign of degradation to the Pyrite and the Stannite is undamaged. A really attractive setting for the dark sulfides nestled in a golden matrix.
Franckeite has always been an incredibly rare mineral and was only known in micro crystals until the major find in 2004 of what was then called Potosiite. This is now known to be a variety of Franckeite with less tin than usual. This was not a large find but the better specimens were quickly gobbled up by collectors and are almost never available now. This piece was one of those major specimens, it is from a collection we are liquidating for the owner and retains the original Kosnar label. In incredible condition for this delicate mineral with individual crystals that reach over 1 CM, in clusters and free standing masses. This piece also has crystals of the original Franckeite that is not the Potosiite variety so this brings two of the world's rarest Sulfosalts on a single matrix. For the species, this is also an esthetic piece, with very three dimensional form and a good metallic luster.
Fine Phosphophyllite crystals nearly fill the void of a fossil clam shell with the center area still open. The center void has dozens of sharp terminations surrounding the middle. Some crystals show the classic "swallowtail" twinning habit and all are a translucent apple green. This is one of the very best specimens I have seen from a small find made in 2009-2010. Phosphophyllite in sizable crystals is rare and one of the "holy grail" species. Outside of Bolivia nearly all other specimens are quite small, measured in millimeters, and most are micros. This locality is about 45 KM from the more famous mines at Cerro Rico which is also in Potosi, Bolivia. The best specimens from Cerro Rico are highly prized, being both rare and some the most expensive mineral specimens in the world. This smaller find at Huaylliani more than a decade ago was huge news in the mineral world back then. While the crystals from here are not as gemmy and clear as the best from Potosi, they are still very fine and would rank as the second best in the world. The find is long ago finished and these are now quite prized as well. The largest crystals on this piece are over 2 CM but most are smaller. An unusual piece, very large for the area, this has both lustrous areas and some lightly frosted crystal faces. Minimal matrix, this is over 78 grams of nearly pure Phsopophyllite. The shape of the clam shell is still somewhat visible on the backside but the open vug of the green Phosphophyllite crystals is the real star here. In excellent condition overall, a few small Iron stains are present on some edges though the crystals are very clean. An outstanding piece from this important find.
Paravauxite and Wavellite on Quartz
Siglo XX mine, Llallagua, Bustillos Province
10.4 x 7.3 x 4.3 CM (cabinet)
Early summer 2021
A superb large cabinet specimen of very fine aesthetic composition. A plate of Quartz crystals are entirely encrusted with tiny sparkling prisms of clear Paravauxite and a few scattered balls of Wavellite. In fantastic condition as seen, this is a very rich specimen of these two Phosphates and has a subtle creamy yellow to greenish tint best seen in person. The balls of Wavellite reach 1.5 CM and are composed of creamy radiating crystals with a pearly luster. The Paravauxite crystals are more equant prisms than the typical flat habit, the luster and transparency is excellent. Though those crystals are small the overall display impact and three dimensional architecture is superb for the specie.