mineral

Quartz

Silicon Dioxide (SiO2)

Hardness of 7 on the Mohs scale, typically white or transparent, vitreous luster, hexagonal crystal system, conchoidal fracture with no true cleavage, specific gravity of 2.65.

Identified August 1, 2026More mineral →

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Physical properties

Hardness of 7 on the Mohs scale, typically white or transparent, vitreous luster, hexagonal crystal system, conchoidal fracture with no true cleavage, specific gravity of 2.65.

Formation & geological history

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

Uses & applications

Used in electronics, watches, glassmaking, abrasives, and as a semi-precious gemstone or collector's specimen.

Geological facts

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

Field identification & locations

Easily identified by its hardness (scratches glass), lack of cleavage, and characteristic conchoidal fracture. Found worldwide in nearly all types of geological formations.