The name lapis means stone. Lazuli is derived from the Persian lazhward, meaning blue. This is also the root of our word, azure.
Lapis lazuli is one of the oldest of all gems, with a history stretching back some 7000 years or more. This mineral is important not just as a gem, but also as a pigment, for ultramarine is produced from crushed lapis lazuli. (This is why old paintings used ultramarine for their blue pigments and never fade.)
Lapis is between 5 and 6 on the Mohs scale, depending on its composition. With care, lapis jewelry and carvings can delight their owners for generations. Its toughness is considered Fair.
- Mineral: Rock
- Chemical composition: An aggregate
- Color: Greenish blue to violetish blue
- Refractive index: 1.500, sometimes 1.670
- Birefringence: None
- Specific gravity: 2.75 (+/- 0.25)