mineral

Smoky quartz

Quartz (silicon dioxide, SiO₂)

AI-generated identification · may be incorrect

Translucent smoky-brown to gray crystal with a vitreous luster and likely hexagonal crystal form. Mohs hardness 7; no cleavage, with conchoidal fracture; specific gravity about 2.65.

Identified October 4, 2026More mineral →

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Physical properties

Translucent smoky-brown to gray crystal with a vitreous luster and likely hexagonal crystal form. Mohs hardness 7; no cleavage, with conchoidal fracture; specific gravity about 2.65.

Formation & geological history

Forms in silica-rich pegmatites and hydrothermal veins, commonly growing in cavities in granite. The brown color usually results from natural irradiation of trace aluminum-bearing quartz; the specimen’s age cannot be determined from the image.

Uses & applications

Used as a gemstone, in jewelry and carving, and as a collectible mineral specimen.

Geological facts

Quartz is one of Earth’s most abundant minerals; smoky coloration can range from pale gray to nearly black.

Field identification & locations

Look for glassy luster, hardness sufficient to scratch glass, and absence of cleavage. Common localities include Brazil, the Alps, Madagascar, and parts of the United States; the image alone cannot confirm the identification.