Noun
lazurite (usually uncountable, plural lazurites)
(mineralogy) A mineral of metamorphosed limestones. Lazurite forms the gemstone lapis lazuli, and crushed lazurite provided the ultramarine color in artists' paint of the Old Masters. Sodalite and lazurite form the sodalite group of silicate minerals. Chemical composition: Sodium aluminum silicate with sulphur, Na4-5Al3Si3O12S.
Lazurite is a deep blue to greenish blue. Source: Internet