mineral

Black Tourmaline

Schorl (NaFe2+3Al6(Si6O18)(BO3)3(OH)4)

Hardness: 7 to 7.5 on the Mohs scale. Color: Deep black, opaque. Luster: Vitreous to sub-metallic. Crystal structure: Trigonal, typically forming prismatic crystals with vertical striations and a triangular cross-section. Cleavage: Indistinct, breaks with conchoidal fractures. Specific gravity: 3.2 to 3.8.

Hardness: 7 to 7
Color: Deep black, opaque
Luster: Vitreous to sub-metallic

Identified August 5, 2026More mineral →

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Physical properties

Formation & geological history

Forms primarily in pegmatites, hydrothermal veins, and metamorphic rocks such as schists and gneisses through the crystallization of boron-rich fluids associated with cooling magma.

Uses & applications

Widely used in mineral collecting, metaphysical practices, jewelry (when cut or polished), and occasionally in industrial applications due to its pyroelectric and piezoelectric properties.

Geological facts

Schorl is the most common variety of tourmaline, accounting for about 95% of all tourmaline in nature. Its name is derived from a village in Saxony, Germany.

Field identification & locations

Easily identified by its characteristic prismatic crystal habit, distinct triangular cross-sections, and deep vertical striations on the crystal faces. Commonly found worldwide, including Brazil, Pakistan, the United States, and Madagascar.

Other mineral specimens

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Sandstone (with potential mineral staining/concretions)

Arenite (SiO2 based)

sedimentary

Soil with Mineral Detritus and Quartz Fragments

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FeO(OH)·nH2O / FeO(OH)

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Septarian Pebble

Septarian nodule / Concretion

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Schist

Metamorphic

Potassium Feldspar (Orthoclase)

Orthoclase (KAlSi3O8)

mineral