Lapis Lazuli

Physical Properties

Hardness: 5-5.5 (Mohs scale). Color: Intense deep blue to light blue. Luster: Dull to vitreous. Crystal Structure: Isometric (for lazurite component). Cleavage: Imperfect. Specific Gravity: 2.7-2.9. Features gold-colored pyrite inclusions and white calcite veining.

Formation & Geological History

Formed through contact metamorphism, where heat and pressure from magmatic intrusions transform limestone or dolomite into marble and introduce sulfur, creating the blue mineral lazurite. Found in deposits dating back over 6,000 years.

Uses & Applications

Primarily used in jewelry, ornamental carvings, and pigments (ultramarine). Historically used for amulets, cylinder seals, and in the funeral mask of Tutankhamun.

Geological Facts

Lapis lazuli was the source of the world's most expensive pigment, ultramarine, which was used by Renaissance artists like Vermeer and Michelangelo. The finest material has historically come from the Sar-e-Sang mines in Afghanistan.

Field Identification & Locations

Identify by its characteristic royal blue color combined with flecks of gold pyrite and white calcite. In the field, look for crystalline marble associations. Major deposits are in Afghanistan, Chile, Russia, and Canada.

Identified on: 5/7/2026

Mode: Standard