mineral

Quartz Crystal

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale. Color: Clear, white, gray, yellowish, or smoky. Luster: Vitreous (glassy). Crystal Structure: Trigonal. Cleavage: None. Specific Gravity: 2.65.

Hardness: 7 on Mohs scale
Color: Clear, white, gray, yellowish, or smoky
Luster: Vitreous (glassy)

Identified July 31, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale. Color: Clear, white, gray, yellowish, or smoky. Luster: Vitreous (glassy). Crystal Structure: Trigonal. Cleavage: None. Specific Gravity: 2.65.

Formation & geological history

Formed in a wide variety of geological environments, commonly in hydrothermal veins, pegmatites, and as a primary constituent of igneous, metamorphic, and sedimentary rocks.

Uses & applications

Used in electronics, oscillators, watches, glassware, gemstones, and abrasive materials.

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.

Field identification & locations

Identified by its conchoidal fracture, lack of cleavage, high hardness (scratches glass), and distinct vitreous luster. Found globally in almost every geological setting.