Lapis lazuli is a deep blue opaque rock with sparkling inclusions of metal pyrites. One of the few rocks used as a gem, lapis lazuli is composed of grains of several blue minerals, including lazurite and sodalite. This complex, opaque gemstone additionally has a matrix of calcite and speckles of pyrite. It is distinctively fluorescent. The rich blue color is due to the sulfur inherent in the structure of lazurite. Lapis lazuli is thought of by many people around the world as the gemstone of truth and friendship.
