Rock Identifier
Malachite (Copper carbonate hydroxide [Cu2CO3(OH)2]) — Mineral
Mineral

Malachite

Copper carbonate hydroxide [Cu2CO3(OH)2]

Hardness: 3.5–4.0 Mohs; Color: Bright green, dark green, blackish green, often with distinct concentric bands; Luster: Silky, velvety, or dull; Crystal structure: Monoclinic; Cleavage: Perfect; Specific Gravity: 3.6–4.0.

Hardness
3
Luster
Silky, velvety, or dull
Identified More mineral

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Physical properties

Hardness: 3.5–4.0 Mohs; Color: Bright green, dark green, blackish green, often with distinct concentric bands; Luster: Silky, velvety, or dull; Crystal structure: Monoclinic; Cleavage: Perfect; Specific Gravity: 3.6–4.0.

Formation & geological history

A secondary mineral that forms in the oxidized zones of copper ore deposits. It typically forms from the weathering of copper minerals like chalcopyrite or bornite when they react with carbonated water. Found in hydrothermally altered environments.

Uses & applications

Used primarily as a semi-precious gemstone for jewelry, ornamental carvings, and decorative inlay (pietre dure). Historically used as a green pigment in paints until the 1800s and as a minor ore of copper.

Geological facts

Ancient Egyptians used malachite for amulets and as eye shadow as early as 4000 BC. Large deposits in the Ural Mountains of Russia fueled the creation of massive 'Malachite Rooms' in palaces. It is often found associated with the blue mineral Azurite.

Field identification & locations

Identify in the field by its distinct vibrant green color and botryoidal (grape-like) or banded appearance. It is soft and will effervesce (fizz) slightly when in contact with dilute hydrochloric acid. Major sources include the Democratic Republic of the Congo, Russia, Namibia, and Arizona, USA.