Brochantite is a secondary Copper mineral formed in the oxidation zone of primary Copper deposits. It can range in color from emerald green to black-green to blue-green with a vitreous (glassy) to silky luster, often occurring in association with Cuprite, Atacamite, Malachite, Quartz, Cyanotrichite and Azurite.
The crystal system for Brochantite is monoclinic, often forming needle-like acicular aggregates of crystal clusters and druzy and fibrous crusts. Other forms include grainy, massive and occasionally a pseudomorph (original mineral replaced by another while retaining original shape) after Azurite Malachite and Chrysocolla.
Brochantite is found in a number of locations around the world, notably Australia, Chile, China, DR Congo, Mexico, Morocco, Namibia and the USA (Arizona, New Mexico and Nevada).