The nice thing about malachite is that no two pieces will ever be quite the same….even when cut from the same stone. Malachite is an oxide of copper, forming when oxygen combines with copper to cause it to bubble up. You can see how the layering of the formation creates the lines that run through the stone when it is cut. Malachite is a sister stone to azurite and sometimes forms in conjunction with it. It is a beautiful gemstone that has been used in jewelry and carved artwork for centuries.
Source: Primary source is Democratic Republic of Congo (Zaire), along with Australia, Chile, the US and others.
Chemical: CU2(OH)2CO3
Formation: Along veins of copper ore.
Unusual Properties: A very unusual color scheme with veins of dark to light green.
Colors: A wide array of greens from dark to light in vein formations along the bubble planes of the formation.
Wearability: Fair to good. A bit soft for a ring but wears nicely in necklaces and earrings.
RI: 1.655 – 1.909
Birefringence: .254
Optic Character: Biaxial Negative B-
Specific Gravity: 3.80 average
Crystal System: Monoclinic but rare in crystals
Hardness: 4
Transparency: Opaque
Special Identifying Properties and Tests: None really needed. There is nothing on the market that looks like malachite.
Synthetics: No.
Imitations: None that are really viable.