mineral

Schorl (Black Tourmaline) in Quartz/Feldspar Matrix

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

Hardness: 7-7.5 (Tourmaline) / 6 (Feldspar); Color: Pitch black crystals in white/creamy matrix; Luster: Vitreous to sub-metallic; Crystal structure: Trigonal; Cleavage: Indistinct; Specific gravity: 3.0-3.3

Hardness: 7-7
Color: Pitch black crystals in white/creamy matrix
Luster: Vitreous to sub-metallic

Identified June 24, 2026More mineral →

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Physical properties

Formation & geological history

Formed in granitic pegmatites through hydrothermal activity where boron-rich fluids crystallize. Often found in Precambrian to Cenozoic geological formations.

Uses & applications

Used primarily for mineral specimens, metaphysical collections, and as a source of boron. High-quality crystals are used in jewelry.

Geological facts

Schorl accounts for 95% or more of all tourmaline found in nature. It is pyroelectric, meaning it generates an electrical charge when heated.

Field identification & locations

Identified by vertical striations on elongated black crystals and its high hardness. Commonly found in pegmatite-rich regions like Brazil, Madagascar, and the US (California/Maine).

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Mineral/Rock

Banded Gneiss (River Rock/Pebble)

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Metamorphic Rock

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mineral