mineral

Fluorite (Blue)

Calcium Fluoride (CaF2)

Hardness: 4 on Mohs scale. Color: Deep blue to teal with internal inclusions. Luster: Vitreous (glassy). Crystal structure: Cubic (though this is tumbled/rounded). Cleavage: Perfect octahedral. Specific gravity: 3.175–3.184.

Hardness: 4 on Mohs scale
Color: Deep blue to teal with internal inclusions
Luster: Vitreous (glassy)

Identified March 16, 2026More mineral →

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Physical properties

Formation & geological history

Formed through hydrothermal activity, often as a vein mineral in igneous rocks or as a precipitate in sedimentary settings. It occurs in a variety of geological ages from Paleozoic to more recent formations depending on local tectonic activity.

Uses & applications

Used as a flux in steel making, in the manufacture of hydrofluoric acid, and for high-performance telescoping and camera lenses. In its gemstone form, it is used for jewelry, lapidary art, and metaphysical collecting.

Geological facts

Fluorite is the mineral from which the term 'fluorescence' was derived, as many specimens glow under UV light. It is often called 'the most colorful mineral in the world' because it can occur in every color of the spectrum.

Field identification & locations

Identify in the field by its distinct cubic crystal habit (if not tumbled) and limited hardness; it can be scratched by a steel knife but not by a copper penny. Commonly found in China, Mexico, South Africa, and the Illinois-Kentucky Fluorspar District. Look for vitreous luster and distinct color zoning.