Detailed information
Species
Bournonite
Dimensions
43 x 50 x 32
mm
Locality
Viboras Mine, Machacamarca Cornelio Saavedra Province Potosí Department, Bolivia
Condition
No recorded repairs
This beautifully crystallised small miniature Bournonite is from the Viboras mine in Machacamarca, Bolivia, a small silver mine which is still in operation. Bournonite, commonly called cog wheel ore, is a lead-copper sulphosalt and in this specimen forms characteristic cog wheel crystals to at least 1.8 cm diameter, with well defined, sharp, steel blue to silver black crystals. The Bournonite is associated with granular crystalline clustered druses infilling voids between the crystals, whose species is uncertain and requires microscopic study. An aesthetic Bournonite from this recent find at the Viboras mine in Bolivia.