mineral

Quartz

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: typically white, clear, or cloudy; Luster: vitreous (glassy); Crystal structure: Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Hardness: 7 on Mohs scale
Color: typically white, clear, or cloudy
Luster: vitreous (glassy)

Identified July 5, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: typically white, clear, or cloudy; Luster: vitreous (glassy); Crystal structure: Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Formation & geological history

Quartz forms in a wide variety of environments, including igneous, metamorphic, and sedimentary settings. It crystallizes from cooling magma or hydrothermal veins and can resist weathering to form sand and sandstone.

Uses & applications

Used in glass making, ceramics, jewelry, electronics (due to piezoelectric properties), and as an abrasive in industrial applications.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. It was often used by early civilizations to make tools and weapons due to its hardness and predictable fracture patterns.

Field identification & locations

Identified in the field by its hardness (it scratches glass), lack of cleavage, and glassy appearance. Found globally in mountains, beaches, and riverbeds.