mineral

Quartz

Silicon Dioxide (SiO2)

Hardness of 7 on the Mohs scale; color varies (clear, white, gray, smoky); vitreous (glassy) luster; trigonal crystal system; conchoidal fracture with no true cleavage; specific gravity of 2.65.

Identified July 30, 2026More mineral →

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Physical properties

Hardness of 7 on the Mohs scale; color varies (clear, white, gray, smoky); vitreous (glassy) luster; trigonal crystal system; conchoidal fracture with no true cleavage; specific gravity of 2.65.

Formation & geological history

Forms in a wide variety of geological environments, including igneous, metamorphic, and sedimentary rocks. Often crystallizes from silica-rich hydrothermal veins and pegmatites.

Uses & applications

Used in electronics, watchmaking, glass manufacturing, abrasives, and as gemstones or decorative specimens in jewelry.

Geological facts

Quartz is one of the most abundant and widely distributed minerals found on Earth's continental crust. Its piezoelectric properties make it invaluable in modern technology for frequency control.

Field identification & locations

Easily identified by its high hardness (scratches glass), lack of cleavage, and characteristic hexagonal crystal habit when well-formed. Found worldwide.