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

Chrysocolla

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

Hardness: 2.5-3.5 on Mohs scale; Color: Cyan, blue-green, or emerald green; Luster: Vitreous to dull; Crystal structure: Orthorhombic (usually cryptocrystalline); Specific gravity: 2.0-2.4

Hardness
2
Color
Cyan, blue-green, or emerald green
Luster
Vitreous to dull
Identified More mineral
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Physical properties

Hardness: 2.5-3.5 on Mohs scale; Color: Cyan, blue-green, or emerald green; Luster: Vitreous to dull; Crystal structure: Orthorhombic (usually cryptocrystalline); Specific gravity: 2.0-2.4

Formation & geological history

Secondary mineral formed in the oxidation zones of copper ore bodies. It occurs as encrustations, vein fillings, or botryoidal masses often associated with quartz, malachite, and azurite.

Uses & applications

Informal copper ore, popular minor gemstone for cabochons and beads, and highly sought after by mineral collectors for its vibrant color.

Geological facts

Chrysocolla is often confused with turquoise. The name is derived from the Greek words 'chrysos' (gold) and 'kolla' (glue), referring to the name of the material used to solder gold in ancient times.

Field identification & locations

Identify by its bright blue-green color and lack of reaction to HCl (unlike malachite). It is often found in arid regions like Arizona, Chile, and the Democratic Republic of Congo. Sticks slightly to the tongue due to its high water content.