Lapis lazuli is an opaque blue rock made up of several different minerals, including lazurite, sodalite, hauyne, calcite and pyrite. An intense dark blue colour, with minor patches of white calcite and brassy yellow pyrite is considered to be the best quality. The best quality lapis lazuli is from Afghanistan. Lapis has been used in jewellery since antiquity. During the middle ages it was ground and used as a pigment in painting. Today it is used for ring stones and necklaces. It is a fairly soft stone and chemical contact should be avoided. The safest cleaning procedure for lapis is to wash it in warm soapy water, rinse it and leave it to dry naturally.