2.1" Striking Green Conichalcite Formation - Utah

This is a beautiful formation of striking green conichalcite microcrystals that formed as botryoidal aggregates, associated with brownish goethite. It was collected from the Gold Hill Mining District of Tooele County in western Utah. It closely resembles cornwallite, another green copper-based mineral found in this mine that also forms in botryoidal formations.

Conichalcite is an arsenate mineral that forms as a secondary mineral in the oxidized zones of copper deposits. Often it will bear a vibrant green color, though it will display a variety of colors from grass-green to yellow-green. It is the arsenic-rich end member of the series, and calciovolborthite is the vanadium-rich end member.

Conichalcite contains a significant amount of poisonous arsenic, making it somewhat toxic. Therefore, washing hands following handling of conichalcite specimens is recommended.

Chemical formula: CaCu(AsO4)(OH)

Conichalcite & Goethite
Frankie Mine, Gold Hill Mining District, Tooele County, Utah
Entire Specimen: 2.1 x 1.4"