Bournonite (“cogwheels”) black Good Bolivian Coppers are not

Good Bolivian Coppers are not common on the market

A rare and UN-repaired Tourmaline example from this beloved locality in California

excellent quality

this was one of only a handful of crystals recovered according to my source who acquired them directly at the locality

Bournonite (“cogwheels”) black Good Bolivian Coppers are notA hard to find "cogwheel" group of sharp, thick, blocky modified twinned crystals of Bournonite with excellent metallic luster. The piece displays well from a few angles. The stacked appearance of the crystals, combined with the bright luster, makes this one of the more eye catching smaller Bournonites available. Specimen # BOL711B23