Malachite

Copper(II) carbonate hydroxide [Cu2CO3(OH)2]

Rock Type: mineral

Malachite

Physical Properties

Hardness: 3.5-4.0 Mohs; Color: Bright green, dark green, blackish-green; Luster: Silky, velvety, or dull in aggregate form; Crystal Structure: Monoclinic; Cleavage: Perfect; Specific Gravity: 3.6-4.0.

Formation & Geological History

Formed in the oxidation zones of copper deposits where carbonated waters interact with copper ores. Often found as botryoidal (grape-like) masses or fibrous crusts within limestone environments.

Uses & Applications

Used primarily as decorative stone, gemstones for jewelry, and occasionally as a green pigment in paints. Historically used as a copper ore.

Geological Facts

Malachite often grows alongside blue Azurite. In ancient Egypt, it was used as an eye paint and amulet material to ward off evil spirits. Its distinct banding is caused by variations in copper concentration during formation.

Field Identification & Locations

Identify in the field by its distinct green color and concentric banding. Commonly found in the Democratic Republic of Congo, Russia, Namibia, and Arizona (USA). Note: It reacts with hydrochloric acid (effervesces).

Identified on: 4/28/2026

Mode: Standard