Olivenite n. : An olive-green mineral, a hydrous arseniate of copper; olive ore.

Example:


Taxonomy
Olivenite, free encyclopedia, mineral, crystals, small amount, acicular crystals, the crystals, search, Mammoth Mine, formula, 4O, brilliant, domal, globular aggregates, lamellar, characteristic feature, German, olive-green.

Defination from the web:
Olivenite is a copper arsenate mineral, formula Cu 2As O 4OH. It crystallizes in the orthorhombic system, and is sometimes found in small ... This is found as small dark green crystals resembling olivenite at Libethen in the Slovak Republic, and in small amount also in Cornwall. ...