Mineral Species: Chrysocolla and Malachite

Chemical Formula: CuSiO3.nH2O

Chemical Name: Hydrous Copper Silicate

Mineral Class: Phyllosilicate

Mineral Notes: Chrysocolla is an attractive blue-green colour that is unique in the mineral world. It is perhaps more appropriately regarded as a mineraloid than a true mineral because most of the time it is amorphous. This means that it does not have a coherent crystalline structure. At higher temperatures, however, it does assume some degree of crystallisation adopting a structure that resembles Si4O10 chains.  

Description: A very unusual botryoidal habit of blue-green Chrysocolla. The depth of colour is given by a film of Malachite laying below the crystals of Chrysocolla. The Malachite breaks through in places on the lower surface of the specimen, and where it does so, it is very crystalline and intensely green. A very colourful display specimen.

Location: Katanga, Dem. Rep. of Congo.