mineral

Quartz

Silicon Dioxide (SiO2)

Hardness of 7 on the Mohs scale. Color varies from colorless to white, gray, purple, pink, brown, or black. Luster is vitreous (glassy). Crystal structure is trigonal. Cleavage is absent (conchoidal fracture). Specific gravity is 2.65.

Identified August 7, 2026More mineral →

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Physical properties

Formation & geological history

Forms in a wide variety of geological environments, most commonly as a primary mineral in igneous rocks like granite and pegmatites, in hydrothermal veins, and as detrital grains in sedimentary rocks.

Uses & applications

Used in electronics (oscillators), glassmaking, abrasives, gemstones, and ornamental carvings.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust, surpassed only by feldspar. It exhibits piezoelectric properties, meaning it can generate an electrical charge in response to applied mechanical stress.