Mineral Species: Dolomite

Chemical Formula:  CaMg(CO3)2

Chemical Name: Calcium Magnesium Carbonate

Mineral Class: Carbonate

Mineral Notes: Dolomite is a common sedimentary rock-forming mineral that can be found in massive beds, called Dolomitic Limestone. Debate has raged as to how these beds formed. Dolomite at present time, does not appear to form on the surface of the planet; yet thick layers of the mineral can be found in ancient rocks. That is a huge puzzle for geologists who observe sandstones, shales and limestones deposited today. Why no dolomite? 

Description: A very rare specimen of Cornish Dolomite. The crystals are superbly formed, having a flattened bi-pyramidal habit. The colour is off white with a strong adamantine luster.

Location: Geevor Mine, Pendeen, Cornwall, England.