Caledonite

Formula: Pb5Cu2(SO4)3(CO3)(OH)6

Species: Sulfates

Colour: Dark blue to bluish-green; light bluish green in transmitted light.

Lustre: Vitreous, Resinous

Hardness: 2½ – 3

Specific Gravity: 5.75 – 5.77

Crystal System: Orthorhombic

Name: Named in 1832 after “Caledonia,” an ancient name for Scotland, in view of the initial discovery of the species in Scotland.

Type Locality: Leadhills, South Lanarkshire, Scotland, UK

The carbonate analogue of viskontite.