mineral

Quartz

Silicon Dioxide (SiO2)

Hardness of 7 on the Mohs scale, vitreous luster, conchoidal fracture, lacks cleavage, colorless or white when pure, hexagonal crystal system.

Identified August 3, 2026More mineral →

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Physical properties

Hardness of 7 on the Mohs scale, vitreous luster, conchoidal fracture, lacks cleavage, colorless or white when pure, hexagonal crystal system.

Formation & geological history

Forms in a wide variety of geological environments, including igneous, metamorphic, and sedimentary rocks, often crystallizing from silica-rich hydrothermal solutions or cooling magma.

Uses & applications

Used in electronics, watches, glassmaking, abrasives, and as a gemstone or specimen for collectors.

Geological facts

Quartz is one of the most abundant minerals in Earth's continental crust and exhibits piezoelectric properties, meaning it can generate an electrical charge under mechanical stress.

Field identification & locations

Easily identified by its high hardness (scratches glass), conchoidal fracture, and lack of cleavage. Found worldwide in nearly every type of geological environment.