Blue Apatite

Physical Properties

Hardness: 5 on Mohs scale; Color: Deep teal blue with streaks of green/gray; Luster: Vitreous to sub-vitreous; Crystal Structure: Hexagonal; Cleavage: Poor/Indistinct; Specific Gravity: 3.16–3.22.

Formation & Geological History

Formed in igneous, metamorphic, and sedimentary environments. It is a common accessory mineral in most igneous rocks and is found in pegmatite veins and metamorphic limestone (marbles).

Uses & Applications

A major source of phosphorus for fertilizer. Used as a gemstone and in decorative carvings or polished towers. It is also used as a material for the manufacture of phosphoric acid.

Geological Facts

Apatite is the specific mineral that defines the hardness of 5 on the Mohs scale. The name is derived from the Greek word 'apate', meaning to deceive, because it was often confused with other minerals like tourmaline or beryl.

Field Identification & Locations

Identify by its characteristic teal color and the fact it can be scratched by a steel knife (unlike quartz or beryl). Finding it in hexagonal prismatic forms is common. Found globally with major deposits in Brazil, Madagascar, and Mexico.

Identified on: 4/29/2026

Mode: Standard