Mineral Species: Bornite

Chemical Formula: Cu5FeS4

Chemical Name: Copper Iron Sulfide

Mineral Class: Sulfide

Mineral Notes: Bornite is an important copper ore mineral which is more usually known as Peacock Ore. It does occeasionally occur in a crystalline form, but this is rare. Bornite's crystals, if found, are distorted cubes with curved faces. Sometimes the even rarer distorted octahedrons and dodecahedrons are found.

Description: A very rich specimen of Bornite showing widespread crystalline form. Many individual crystal outlines and faces can be seen. The mineral has a dark grey colour and a very strong metallic luster. Some areas of the mineral are covered by highly crystalline Pyrite. The colour contrast between the two species is very attractive

Location: Dolcoath Mine, Camborne, Cornwall, England.