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Malachite is usually found in opaque green masses; the color is due to the copper content. Crystals are too small for faceting, however the massive material is carved or polished in many ways to reveal the alternating bands of light and dark green. In the past, malachite was worn to ward off danger and illness.

Malachite occurs in small quantities worldwide, but in larger quantities in copper-mining areas. Zaire is the most important producer.

Malachite Properties

Chemical Composition: 
Hydrated copper carbonate - Cu2CO3(OH)2
Colors / Varieties: 
Banded in shades of green, bluish green, yellowish green or blackish green. Banding may be curved or angular.
Transparency: 
Translucent to Opaque.
Crystal System / Forms: 
Monoclinic System / Botryoidal masses with radiating fibrous inner structure, frequently banded, acicular crystals.
Hardness: 
4
Specific Gravity: 
3.80 - 4.00 (Spot R.I.: 3.95
Cleavage / Fracture: 
Cleavage present but rarely observed because of fibrous habit / Uneven fracture.
Optic Character: 
Anisotropic, D.R.; Biaxial negative (generally opaque).
Lustre: 
Sub - vitreous
Refractive Index / Birefringence: 
1.660 - 1.910 (Spot R.I. 1.85) / 0.250;
Pleochroism: 
None.
Magnification: 
Curved and straight banding.
U.V. Fluorescence: 
Inert
Spectrum: 
Not characteristic
Cause of Color: 
Copper
Specific Tests: 
Effervesces with cold hydrochloric acid.
Synthesis: 
First produced in Russia by the ceramic technique. Identical to the natural malachite and cannot be identified by the routine tests.
Simulants (with separation tests): 
Azure-malachite (structure), Synthetic Malachite (elemental analyses), Green Turquoise (structure, R.I., birefringence)
Geological Occurrence: 
Upper zone of copper deposits, found together with azurite and cuprite.
Sources: 
Russia, Australia, South Africa, Zambia, New Mexico.
Cuts & Uses: 
Cabochon, beads, carvings, plaques, for inlay purposes. Sometimes cut along with the associated mineral such as azure-malachite, or along with chrysocolla.