mineral

Fluorite (Durango Fluorite)

Calcium Fluoride (CaF2)

Hardness: 4 on Mohs scale; Color: Variable (this specimen shows deep purple and translucency); Luster: Vitreous; Crystal Structure: Isometric/Cubic; Cleavage: Perfect octahedral; Specific Gravity: 3.175–3.184.

Hardness: 4 on Mohs scale
Color: Variable (this specimen shows deep purple and translucency)
Luster: Vitreous

Identified March 23, 2026More mineral →

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Physical properties

Formation & geological history

Formed through hydrothermal activity where fluorine-rich fluids circulate through fractures in limestone or igneous rocks. This specimen is from Durango, Mexico, which is famous for its diverse mineral deposits formed during various volcanic stages of the Tertiary period.

Uses & applications

Used as a flux in steelmaking (smelting), in the manufacture of high-clarity lenses for telescopes and cameras, as a source for fluorine chemicals, and widely as a decorative carving or collector's mineral specimen.

Geological facts

The word 'fluorescence' is derived from fluorite because many specimens, including those from Durango, glow brilliantly under UV light. It is often called 'The Most Colorful Mineral in the World.'

Field identification & locations

Identify in the field by its distinct 4-directional cleavage, relative softness (can be scratched by a pocket knife but not a copper penny easily), and cubic crystal habit. Durango specimens are highly sought after by collectors for their intense coloration and UV reactivity.

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