mineral

Fluorite (Rainbow Fluorite)

Calcium Fluoride (CaF2)

Hardness: 4 (Mohs scale); Color: Variegated purple, green, and clear/blue; Luster: Vitreous; Crystal system: Isometric/Cubic; Cleavage: Perfect octahedral; Specific Gravity: 3.17-3.19. These pieces are polished 'chips' or 'nuggets'.

Hardness: 4 (Mohs scale)
Color: Variegated purple, green, and clear/blue
Luster: Vitreous

Identified July 21, 2026More mineral →

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Physical properties

Formation & geological history

Formed via hydrothermal activity in veins alongside metallic ores or in sedimentary rocks like limestone. It is a common gangue mineral in lead and zinc deposits. Major deposits are found in China, Mexico, South Africa, and the USA (Illinois).

Uses & applications

Used as a flux for smelting in steelmaking (fluorspar), in the manufacture of high-clarity lenses, opal glass, and extensively in jewelry/beads and for ornamental carvings.

Geological facts

Fluorite is famous for its wide range of colors and is known as the 'most colorful mineral in the world'. It gave its name to the phenomenon of fluorescence because many specimens glow under ultraviolet light.

Field identification & locations

Identify by its distinctive octahedral cleavage planes (visible as internal 'triangles' or fractures), its relative softness (scratched by a steel knife but not a copper penny), and its variegated color banding.