Turquoise

Introduction: Turquoise is world-wide mineral used as a gemstone for jewellery. It occurs as a secondary mineral in some copper deposits and aluminium enriched rocks. Turquoise is the French word for 'Turksish', where it came from, via Iran.

Distribution: Rubicon pegmatites and from Bogenfels in the early 20th century

Composition: Phosphate

Crystal system: Triclinic

Lustre: Waxy, dull, vitreous

Streak: Pale green to white

Hardness: 5-6