mineral

Fluorite

Calcium Fluoride (CaF2)

Hardness: 4 on Mohs scale; Color: Variable, showing purple and green banding; Luster: Vitreous (glass-like); Crystal structure: Isometric (cubic or octahedral); Cleavage: Perfect octahedral in four directions; Specific gravity: 3.175 to 3.184

Hardness: 4 on Mohs scale
Color: Variable, showing purple and green banding
Luster: Vitreous (glass-like)

Identified July 3, 2026More mineral →

Explore Fluorite in the encyclopedia →

Identify your own rocks.

Get a report just like this from any photo, free.

App Store Google Play

Physical properties

Formation & geological history

Formed through hydrothermal activity, typically in veins within carbonate rocks or in association with lead and silver ores. It occurs from the Precambrian to recent times in various geological environments.

Uses & applications

Used as a flux in steel making, in the production of hydrofluoric acid, in high-performance optical lenses, and extensively in jewelry and mineral collecting due to its vibrant colors.

Geological facts

Fluorite is the most colorful mineral in the world. It is the defining mineral for level 4 on the Mohs scale of mineral hardness. Many specimens exhibit fluorescence under ultraviolet light, a phenomenon named after the mineral itself.

Field identification & locations

Identifiable by its 4-sided cleavage fragments, relatively soft surface (scratchable with a knife), and vitreous luster. Commonly found in China, Mexico, South Africa, and the United States (notably Illinois/Kentucky).