Mineral Species: Vivianite, Fe3(PO4)2(H2O)8, Hydrated Iron Phosphate

Mineral Notes: Vivianite comes in a range of colours and usually has a very shiny surface. Many examples are found inside fossil clam shells or attached to fossilised animal bones. The mineral is light sensitive and will darken as the iron oxidises from +2 to +3 and this process is accelerated by light. 

Description: A brown matrix which contains a thick band of Vivianite running part way through the specimen. Closer inspection shows this to be composed of many columnar crystals fused together, and apparent by the vertical striations running lengthways along the surface. The colour is gray with the characteristic metallic luster.

Location: Wheal Betsy Mine, Cornwall, England.