- Greenockite on Cassiterite
- Siglo Veinte Mine, Llallagua, Bustillos Province, Potosi Department, Bolivia
- Small Cabinet, 8.1 x 5.6 x 4.8 cm
- Ex. Philadelphia Academy of Natural Sciences
This piece has several rich pockets of dense microcrystallized orange/red greenockite, in protected cavities of cassiterite ore. A rare oldtime specimen from Llallagua with rich association of the very rare cadmian sulfide greenockite. I have not seen a specimen of this material for sale before, and in fact was not aware that the species had even been found here until I looked it up. This is one of two associated specimens (perhaps once joined), that were collected during the famous 4th Vaux-Academy expedition to Bolivia in 1929-1930, and comes with one of the two original labels that accompanied the box they were in all these years.