Mineral Type - Chrysocolla
A mineral of secondary origin, commonly associated with other secondary copper minerals, it is typically found as glassy botryoidal or rounded masses or bubbly crusts, and as jackstraw mats of tiny acicular crystals or tufts of fibrous crystals. Copper-bearing allophane can look similar.
Transparency: Translucent, Opaque
Colour: Green, bluish green, blue, blackish blue to black, or brown and rarely yellow
Streak: Light green
Hardness: 2½ - 3½ on Mohs scale.
Tenacity: Brittle
Cleavage: None Observed None
Fracture: Irregular/Uneven, Sub-Conchoidal
Density: 1.93 - 2.4 g/cm3 (Measured)
Elements listed: Al, Cu, H, O, Si
Cell Parameters: a = 5.7 Å, b = 8.9 Å, c = 6.7 Å
Unit Call V: 339.89 ų (Calculated from Unit Cell)
Morphology: Most often found as cryptocrystalline to amorphous botryoidal aggregates and crusts. Crystals reported as fine acicular to fibrous, very rare
Twinning: None reported
Name
The name was first used by Theophrastus in 315 B.C. and comes from the Greek chrysos, meaning "gold," and kolla, meaning "glue," in allusion to the name of the material used to solder gold. André-Jean-François-Marie Brochant de Villiers revived the name in 1808.Physical Properties
Lustre: Vitreous, Waxy, EarthyTransparency: Translucent, Opaque
Colour: Green, bluish green, blue, blackish blue to black, or brown and rarely yellow
Streak: Light green
Hardness: 2½ - 3½ on Mohs scale.
Tenacity: Brittle
Cleavage: None Observed None
Fracture: Irregular/Uneven, Sub-Conchoidal
Density: 1.93 - 2.4 g/cm3 (Measured)
Chemical Properties
Formula: Cu2-xAlx(H2-xSi2O5)(OH)4 · nH2OElements listed: Al, Cu, H, O, Si
Crystallography
Crystal System: OrthorhombicCell Parameters: a = 5.7 Å, b = 8.9 Å, c = 6.7 Å
Unit Call V: 339.89 ų (Calculated from Unit Cell)
Morphology: Most often found as cryptocrystalline to amorphous botryoidal aggregates and crusts. Crystals reported as fine acicular to fibrous, very rare
Twinning: None reported