Lapis Lazuli: Origins and Characteristics
Lapis lazuli is a vividly blue rock known for its striking color and use as a semi-precious gemstone.
Composition and Coloration
- Lapis lazuli derives its blue color primarily from the mineral lazurite, which makes up 25-40% of the rock.
- The intensity of the blue depends on the amount and structure of sulfur in lazurite.
- Presence of calcite can reduce the blueness, while pyrites add a golden sparkle.
- Other minor minerals include diopside and sodalite.
Geographical Significance
- Found in several countries, including Chile, Russia, and the US.
- However, the highest quality is sourced from the Badakhshan province in Afghanistan, with mining dating back over 6,000 years.
Historical Importance
- Used in trade by ancient Indian traders from Badakhshan since around 1000 BC.
- Ornaments made of lapis lazuli were discovered in Indus civilization sites like Mohenjo-daro and Harappa.
- The ancient Egyptians utilized it for jewelry and as a material for eye shadow.
- During the Renaissance, European artists ground it into ultramarine, a costly pigment for painting.
Etymology
- The name "lapis lazuli" is derived from two languages:
- Lapis: Latin for 'stone'
- Lazuli: From the Persian word lazhw ard, meaning 'blue'.
