mineral

Black Tourmaline

Schorl (NaFe3Al6(Si6O18)(BO3)3(OH,F)4)

AI-generated identification · may be incorrect

Hardness: 7-7.5 on the Mohs scale, Color: Pitch black, Luster: Vitreous to submetallic, Crystal structure: Trigonal with striated prismatic crystals, Cleavage: Indistinct, Specific gravity: 3.2-3.8

Hardness: 7-7

Identified August 1, 2026More mineral →

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Physical properties

Hardness: 7-7.5 on the Mohs scale, Color: Pitch black, Luster: Vitreous to submetallic, Crystal structure: Trigonal with striated prismatic crystals, Cleavage: Indistinct, Specific gravity: 3.2-3.8

Formation & geological history

Forms in pegmatites and hydrothermal veins, as well as metamorphic rocks like schists and gneisses, typically associated with cooling magmatic fluids.

Uses & applications

Widely used in jewelry, metaphysical and healing practices, and industrial applications due to its pyroelectric and piezoelectric properties.

Geological facts

Black tourmaline is known scientifically as schorl, which accounts for about 95% of all tourmaline in nature. It was historically referred to by various names like schorl until the 18th century.

Field identification & locations

Easily identified by its deep black color, vitreous luster when tumbled or polished, and striations often visible on raw prismatic faces. Found globally, notably in Brazil, Pakistan, and the USA.