Rock Identifier
Chrysocolla (Hydrated copper phyllosilicate, (Cu,Al)2H2Si2O5(OH)4·nH2O) — mineral
mineral

Chrysocolla

Hydrated copper phyllosilicate, (Cu,Al)2H2Si2O5(OH)4·nH2O

Hardness: 2.5 to 3.5 on the Mohs scale. Color: Green, blue-green, or cyan, often mottled with brown or black. Luster: Vitreous to earthy or dull. Crystal structure: Orthorhombic (though rarely found as distinct crystals, usually amorphous or botryoidal). Cleavage: None. Specific gravity: 2.0 to 2.4.

Hardness
2
Luster
Vitreous to earthy or dull
Identified More mineral
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Physical properties

Hardness: 2.5 to 3.5 on the Mohs scale. Color: Green, blue-green, or cyan, often mottled with brown or black. Luster: Vitreous to earthy or dull. Crystal structure: Orthorhombic (though rarely found as distinct crystals, usually amorphous or botryoidal). Cleavage: None. Specific gravity: 2.0 to 2.4.

Formation & geological history

Formed in the oxidation zones of copper ore bodies, typically as a secondary mineral resulting from the alteration of primary copper minerals. Often found in arid regions and hydrothermal environments.

Uses & applications

Primarily used as an ornamental stone, in cabochons for jewelry, and as a collector's mineral specimen.

Geological facts

Chrysocolla is often confused with turquoise due to its similar coloration and waxy luster, but it is significantly softer. The name comes from the Greek words 'chrysos' (gold) and 'kolla' (glue), referencing its historical use in soldering gold.

Field identification & locations

Can be identified by its vibrant blue-green color combined with a relatively low hardness (easily scratched by a copper penny) and association with copper deposits. Found globally in places like the USA (Arizona), Chile, Peru, and Russia.