Lapis Lazuli

Lapis Lazuli (Rock containing Lazurite, Calcite, and Pyrite)

Rock Type: metamorphic

Lapis Lazuli

Physical Properties

Hardness: 5 to 5.5 on Mohs scale; Color: Intense deep blue with white (calcite) and brassy (pyrite) inclusions; Luster: Vitreous to dull; Crystal structure: Aggregate/Isotropic; Specific gravity: 2.7 to 2.9.

Formation & Geological History

Formed primarily by contact metamorphism of limestone or marble. It is a metamorphic rock that results from the high-temperature alteration of carbonate rocks by intrusive igneous bodies.

Uses & Applications

Extensively used in jewelry (cabochons, beads), decorative carvings, and historically as a pigment (ultramarine) for painting.

Geological Facts

Lapis lazuli was highly prized by ancient Egyptians, who used it for amulets and the funeral mask of Tutankhamun. The name comes from the Latin word 'lapis' for stone and the Persian word 'lazhuward' for blue.

Field Identification & Locations

Identify by its characteristic 'royal blue' color and the presence of gold-colored pyrite specks. Most high-quality specimens come from the Sar-e-Sang mines in Afghanistan. Collectors look for a deep blue color with minimal white calcite.

Identified on: 5/10/2026

Mode: Standard