Fluorite (calciumfluoride) or fluorspar is a mineral occurring in many different colours, found in veins where it's the main mineral or with metallic ores, especially lead and silver. It is common in dolomites and limestone and is associated with many different minerals. It is used chiefly as a flux in the making of steel, and also for enamelling, and in the preparation of hydrofluoric acid. It has the formulae CaF2 and a relative hardness of 4. Research Fluorite