Name:
Malachite
Chem:
Cu2CO3(OH)2
basic copper carbonate
Crystal:
Monoclinic (usually not crystalline, often botryoidal masses)
Color:
light green --> dark green
Refrac. Index:
1.65 - 1.91
Birefraction:
0.021
Hardness:
4
Spec. Grav.:
3.8
Fracture:
splintery
Cleavage:
perfect
Environment:
oxidation zone of copper deposits
Association:
azurite, limonite, chalcopyrite
Locals:
| Ar., Calif., Nev, USA | Zaire | Chile | USSR |
Misc:
The name derived from the Greek word "malache", meaning "mallow" in reference to its green color or "malakos", meaning soft. Easily damaged by acids like all carbonates, and when subjected to heat it turns black.
Gem info:
Cut stones (usually cabochon) have been used since ancient Egyptian times as amulets, carvings, and even as powder for eye shadow. It has been used as a pigment for green paint. Today the best material comes from Zaire, Africa, is cut into cabs of all sizes. Less valuable than turquoise, jade, and lapis.
eye sample
line sample
azur-malachite
