mineral

Schorl (Black Tourmaline)

Sodium Iron Aluminum Borosilicate Hydroxide - NaFe2+3Al6Si6O18(BO3)3(OH)3OH

Hardness: 7-7.5 on Mohs scale. Color: Inky black to brownish-black. Luster: Vitreous to resinous. Crystal Structure: Trigonal (hexagonal/prismatic with vertical striations). Cleavage: Indistinct. Specific Gravity: 3.06 - 3.21.

Hardness: 7-7
Color: Inky black to brownish-black
Luster: Vitreous to resinous

Identified March 23, 2026More mineral →

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Physical properties

Formation & geological history

Formed primarily in pegmatites through hydrothermal processes. It can also be found in high-grade metamorphic rocks like gneisses and schists. It is a common accessory mineral in granitic environments.

Uses & applications

Used as a gemstone for beads and pendants, in scientific instruments for its pyroelectric properties, and widely sold in the metaphysical community for 'grounding' and 'protection' purposes.

Geological facts

Schorl is the most common member of the tourmaline group, accounting for 95% of all tourmaline in nature. It is strongly pyroelectric, meaning it generates an electric charge when heated, which can cause it to attract dust or small debris.

Field identification & locations

Identify in the field by its deep black color, lack of transparency, and distinct vertical striations on elongated prismatic crystals. Common locations include Brazil, Namibia, Madagascar, and the United States (California and Maine).

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Mineral/Rock

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