Bismuthinite with Marcasite

This is a fantastic crystal cluster of Bismuthinite from the Tazna Mine in Bolivia. It consists of many, large, terminated, prismatic crystals of Bismuthinite to 4.6 cm in length. There must be over a dozen, multiply divergent, gray metallic, prismatic crystals of this uncommon bismuth sulfide that comprise this handsome piece. The slender crystals vary in length from a quarter inch to almost two inches in length with many of them terminated. The terminations as well as the prism edges are complete and many of the crystals display a subdued, yellow-gray metallic patina from from a thin coating of Marcasite that coats the crystals. A few, small, unoxidized and broken crystals around the periphery show the bright, gray-white metallic nature of the Bismuthinite crystals. The Tazna Mine is a historic bismuth-tungsten mine in the high Andes of Bolivia that has produced noteworthy specimens for decades. This is from the Rock Currier collection, acquired on his many travels to that country as he helped open it up to mineral specimen exports.