Calcite, CaCO3 (Calcium Carbonate), is one of the commonest minerals, being the main constituent of limestone. Calcite is often fluorescent, a small amount of Managnese is enough to make it glow red under UV light. The mineral will bubble in acid distinguishing it from many similar species, even other carbonates which do not dissolve so easily in cold acids.

Description: Hundreds of perfectly hexagonal crystals covering a grey matrix. The crystals vary widely in size from 1cm down to those that can only be seen magnified. All have excellent terminations and most show a high degree of transparency. A very characteristic soapy luster which is very attractive under a strong light.

Location: Leiyang, Hunan, China.