Detailed information
Species
Stannite, Jamesonite
Dimensions
21 x 28 x 21
mm
Weight
16 g
Locality
San José Mine Oruro City, Cercado Province Oruro Department, Bolivia
Condition
No recorded repairs
Thick, robust, steely-grey metallic prismatic to acicular Jamesonite crystals forming sub-parallel groupings and the occasional criss-crossing crystal sit upon a small cluster of brassy-grey, 'rounded' Stannite crystals. Both species are rare worldwide, but are unusually well-crystallized in a small area of Bolivia famous for tin mining. The San José mine in Oruro Department is one of the most famous mines in the district and has produced an impressive array of unusual sulphosalt species in fine crystals from the 1970s onwards. Although smaller miniature in size the Jamesonite crystals reach over 2 cm in length. There is much damage to the edges of the Jamesonite crystals, but it is rare to see a specimen from San José mine without some bruising and these are particularly large and thick crystals for this rare lead iron sulphosalt species. The Jamesonite crystals extend into the Stannite, skewering the brassy crystals on the back of the specimen. The Stannite crystals, which reach up to 7 mm across, are aggregated, with their crystal faces aligned such that light reflects of all of the crystals at the same time. Although well-crystallized all of the crystals are slightly distorted where the Jamesonite crystals skewer them.