The Probert Encyclopaedia of Rocks & Minerals

CINNABAR

Cinnabar (vermilion) is a red crystalline form of mercuric sulphide. It has the formulae HgS and a relative hardness of 3. It often has a bright red colour. The only important source of mercury and it's found in few localities. Occurs as vein fillings near recent volcanic rocks and hot springs. Used in scientific equipment, in drugs, and with tin in silvering mirrors. Many other uses.
Research Cinnabar