Cause of Color :
Chemical Composition :
Copper Carbonate (unstable state) – Cu3(CO3)2(OH)2
Classification / Type :
The unstable state alters to malachite and is generally found in combination as azumalachite.
Crystal System / Forms :
Monoclinic System / Prismatic crystals, botryoidal, stalagmatic, massive, banded.
Cuts & Uses :
Cabochons, beads, carvings.
3.5 - 4
Vitreous to waxy
Optic Character :
Anisotropic, D.R.; Biaxial positive
Distinct shades of blue (in single crystal)
Refractive Index / Birefringence :
1.730 – 1.840 / 0.110
Simulants (with separation tests) :
Azurmalachite (structure), Lapis Lazuli (structure, R.I., S.G.), Chrysocolla (structure, R.I., S.G.)
U.S.A. (Arizona), Namibia, France, Romania, Australia, Siberia.
Specific Tests :
Attacked by hydrochloric acid, light blue streak.