CONICHALCITE
Conichalcite is a scarce calcium copper hydroxy-arsenate mineral (CaCu(AsO4)(OH)).
It occurs in the altered (oxidized) zones of copper deposits that have
arsenic-bearing minerals. Conichalcite has a nonmetallic luster, greenish
color & streak, is somewhat hard (H = 4.5), is somewhat heavy for its size
(due to the copper content), and has no cleavage. It typically forms
crusts of small, fibrous- to needle-shaped crystals, or forms botryoidal
masses.
Conichalcite from the Higgens Mine near Bisbee, Cochise County, southeastern
Arizona, USA (CSM # 50611, Colorado School of Mines Geology Museum, Golden,
Colorado, USA).