atacamite
noun
at·a·cam·ite
ˌatəˈkaˌmīt,
əˈtakəˌm-
plural -s
: a mineral Cu2Cl(OH)3 consisting of a basic copper chloride that is transparent or translucent and of various shades of green and occurs usually in prismatic orthorhombic crystals but also in crystalline aggregates or in massive form (hardness 3–3.5, specific gravity 3.75–3.77)
Word History
Etymology
French, from Atacama desert, its locality + French -ite