mineral

Rough Topaz

Aluminum silicate fluoride hydroxide (Al2SiO4(F,OH)2)

AI-generated identification · may be incorrect

Hardness: 8.0 on Mohs scale. Color: Pale yellow to colorless. Luster: Vitreous to sub-vitreous. Crystal Structure: Orthorhombic. Cleavage: Perfect basal (one direction). Specific Gravity: 3.4 to 3.6.

Hardness: 8
Color: Pale yellow to colorless
Luster: Vitreous to sub-vitreous

Identified July 10, 2026More mineral →

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Physical properties

Hardness: 8.0 on Mohs scale. Color: Pale yellow to colorless. Luster: Vitreous to sub-vitreous. Crystal Structure: Orthorhombic. Cleavage: Perfect basal (one direction). Specific Gravity: 3.4 to 3.6.

Formation & geological history

Formed by fluorine-bearing vapors given off during the last stages of the crystallization of igneous rocks. It is most commonly found in pegmatite dikes, rhyolite lava flows, and alluvial deposits.

Uses & applications

Frequently used as a gemstone in jewelry when faceted; industrial uses include use as an abrasive in some glass-making processes due to high hardness.

Geological facts

Topaz is one of the hardest minerals found in nature. A common misconception is that all yellow gemstones are topaz, but true topaz is chemically distinct and much heavier/harder than citrine quartz.

Field identification & locations

Identified in the field by its high hardness (scratches quartz), high density (it feels heavy for its size), and its characteristic crystal shape or basal cleavage. Commonly found in Brazil, Pakistan, and Russia.