mineral

Black Tourmaline (Schorl)

Schorl (Sodium iron aluminum borosilicate hydroxide) NaFe3Al6(BO3)3Si6O18(OH)4

AI-generated identification · may be incorrect

Hardness: 7-7.5 (Mohs), Color: Inky black, Luster: Vitreous to sub-resinous, Crystal Structure: Trigonal/Hexagonal, Specific Gravity: 3.1-3.2

Hardness: 7-7

Identified July 5, 2026More mineral →

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Physical properties

Hardness: 7-7.5 (Mohs), Color: Inky black, Luster: Vitreous to sub-resinous, Crystal Structure: Trigonal/Hexagonal, Specific Gravity: 3.1-3.2

Formation & geological history

Typically found in granitic pegmatites, high-temperature hydrothermal veins, and metamorphic rocks such as schists and marbles. It forms through late-stage crystallization of cooling magma.

Uses & applications

Mainly used as a gemstone, in jewelry, and highly popular for metaphysical/collecting purposes. Due to its piezoelectric properties, it has historical use in pressure gauges.

Geological facts

Black tourmaline is both piezoelectric (generates electricity under pressure) and pyroelectric (generates electricity when heated), which allows it to attract light particles like dust.

Field identification & locations

Identify by its deep black color, vertical striations (if raw), and hardness. It is commonly found in Brazil, Africa, and parts of the United States like Maine and California.