CONICHALCITE (miniature)

Conichalcite, with the chemical formula CaCu(AsO4)(OH), is a fairly prevalent arsenate mineral closely associated with duftite (PbCu(AsO4)(OH)). Characterized by its green, often botryoidal appearance, it typically forms in the oxidation zones of various metal deposits. This mineral is commonly found alongside limonite, malachite, beudantite, adamite, cuproadamite, olivenite, and smithsonite. 

In the oxidation zones of copper orebodies, conichalcite develops as groundwater rich in oxygen interacts with copper sulfide and copper oxide, leading to the formation of minerals like malachite, azurite, and linarite. It is frequently observed encrusting limonitic rocks, which display yellow to red hues. Additionally, conichalcite participates in a solid solution series with calciovolborthite, where arsenic and vanadium are the two interchangeable elements. In this series, conichalcite represents the arsenic-rich end member, while calciovolborthite is the vanadium-rich counterpart.