Lapis Lazuli is a metamorphic rock composed primarily of the blue mineral Lazurite, along with Calcite, Pyrite, and other silicate minerals. It forms through the contact metamorphism of limestone, where intense heat and pressure transform the original sedimentary rock over geological time.
The stone's characteristic deep blue color comes from Lazurite, while golden metallic flecks are Pyrite inclusions and white streaks are Calcite. The quality and appearance vary significantly based on the ratio of these constituent minerals—the most valued specimens contain high concentrations of lazurite with minimal calcite veining.
The primary source remains the Sar-i Sang mines in Afghanistan's Badakhshan province, where Lapis Lazuli has been extracted for over 6,000 years. These deposits formed approximately 20-30 million years ago during the collision of the Indian and Eurasian tectonic plates.
The rock's crystalline structure creates its distinctive opacity and waxy to vitreous luster. Its hardness ranges from 5-6 on the Mohs scale, meaning careful handling is required to prevent chipping along natural fracture lines.