mineral

Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Hardness: 7 on the Mohs scale. Color: Colorless and transparent. Luster: Vitreous (glassy). Crystal Structure: Trigonal, typically forming hexagonal prisms terminated by six-sided pyramids. Cleavage: None (conchoidal fracture). Specific Gravity: 2.65.

Hardness: 7 on the Mohs scale
Color: Colorless and transparent
Luster: Vitreous (glassy)

Identified August 5, 2026More mineral →

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Physical properties

Formation & geological history

Formed in a wide range of geological environments, most notably in hydrothermal veins, pegmatites, and as a primary constituent of igneous, metamorphic, and sedimentary rocks over millions of years.

Uses & applications

Used in electronics, oscillators, optics, glassware, abrasive materials, and extensively in gemstone carving and jewelry.

Geological facts

Quartz is one of the most abundant minerals in Earth's continental crust. Ancient civilizations believed clear quartz was eternal ice frozen by the gods so deeply it could never thaw.

Field identification & locations

Easily identified by its distinct hexagonal crystal habit, conchoidal fracture, and hardness of 7 which easily scratches glass. Found globally, commonly in river gravels, veins, and pegmatite pockets.