Vauxite on Wavellite
Siglo XX mine, Llallagua
5.7 x 3.7 x 1.8 CM (cabinet)
Excellent, well crystalized Vauxite on a botryoidal crystalline Wavellite matrix. The Vauxite has a fine blue color that is a lot more lustrous and vivid than typical. The surface of the display face is thickly encrusted with fine small Vauxites that are in exceptional condition. A choice example from the famed Siglo Viente (20th century) Mine which is the type locality and the only source of such fine specimens. This plate is a bit larger than typical too and looks even better in person.
A lustrous cluster of mostly Pyargyrite crystals that at first glance appear a silvery black color. Strong light shows some brilliant red zones of ruby silver, and with magnification are some classic twinned Polybasite crystals as well. Minimal matrix, the associated Sulphides are only seen with magnification. Some edge chipping is noted, not easy to see by naked eye (this is a brittle mineral ) but the main crystals are in fine condition, some with textbook forms. The Pyrargyrites have some unusual habits on this piece, it is an attractive small miniature with very bright flash., could trim to a very strong thumbnail if desired
Sharp replacement of hexagonal Aragonite crystals by native copper. Excellent form, complete on all sides and with classic hexagonal prisms. Slightly hoppered on flat faces, this is formed of two textbook prisms that intersect on one narrow edge. Usually these pseudos are rather crude, it is very special when such sharp detail is preserved.
Cassiterite variety Needle Tin
Minera Monserrat, Challapampa, Poopo Province
5.6 x 5.5 x 3.4 CM (cabinet)
A very unusual specimen from Boliva that looks like an old Cornish "needle tin". A three dimensional matrix densely covered with delicate accicular crystals of brown Cassiterite. In fine condition as seen, ex. Hitchings collection. Especially impressive under magnification, this is an uncommon habit and a well crystallized example.
Vivianite -Single gemmy crystal
Tomokoni Mine, Machacamarca District
4.5 x 2.3 x 1.3 CM (miniature)
A gem clear single crystal with excellent dark green to bluish color, and glasslike luster. Sharp and elegant, this is at its best with some backlight to bring out the inner colors. On the backside some small matrix is adhering, but mostly this is a single, loose crystal. Typical curving of the termination can be seen at some angles. Choice older specimen from 1980 vintage finds, excellent condition.
A killer Potosi Bournonite with large, perfect crystals showing classic form. Complete all around, a perfect floater with no matrix, just big metallic Bournonites in fine condition. The largest crystal is a sizable 3.8 CM and all the crystals have a gleaming gunmetal luster. This is from the remarkable find in 2007-8 which had the very best Bournonites ever seen from Bolivia and some of the best ever found on the planet. This is very much a top percentile specimen from that discovery, a true top shelf piece.
San Antonio Mine
Loayza Province, La Paz department,
5 x 3.4 x 2.2 CM (miniature)
pre Tucson 2015 update
One of the oldest and best localities for fine Cassiterites in the Americas is the La Paz area of Bolivia. This specimen has well formed and lustrous crystals that under strong lighting show some translucence. The "naked eye" color is shiny black but the "under strong lighting" color is a deep honey orange hue. Some tiny edge chipping exists but most crystals are pristine and the quality for the price is a very good value.
A fine and attractive example of this rare Lead, Silver, Antimony "black ugly" mineral! Until the 2004 find, Andorites were one of the rarer Sulfosalts and crystals were always quite tiny. This piece is from that discovery and a very good value for the size, condition and form. The metallic luster and steel to brassy hues are as good as these ever get. Ex Kosnar, there are now very few of this caliber to be found, lesser pieces are typically far more expensive!