mineral

Quartz

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Clear, white, yellow, or smoky; Luster: Vitreous (glassy); Crystal Structure: Trigonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

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

Identified August 3, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Clear, white, yellow, or smoky; Luster: Vitreous (glassy); Crystal Structure: Trigonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Formed in a wide variety of geological environments, commonly crystallizing from silica-rich hydrothermal veins, within igneous rocks like granite and pegmatite, and as detrital grains in sedimentary rocks.

Uses & applications

Used in jewelry, decorative items, electronics (oscillator crystals), glassmaking, and abrasive products.

Geological facts

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

Field identification & locations

Easily identified by its distinct hexagonal crystal habit (when well-formed), high hardness (scratches glass), and conchoidal fracture. Found globally.