mineral

Quartz

Silicon Dioxide (SiO2)

Hardness: 7 on the Mohs scale. Color: Milky white, clear, or with yellow to brownish iron-staining. Luster: Vitreous to greasy. Crystal structure: Trigonal. Cleavage: None, exhibits conchoidal fracture. Specific gravity: 2.65.

Hardness: 7 on the Mohs scale
Color: Milky white, clear, or with yellow to brownish iron-staining
Luster: Vitreous to greasy

Identified August 7, 2026More mineral →

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Physical properties

Formation & geological history

Forms in a wide variety of geological environments, most commonly as a primary mineral in igneous rocks like granite and pegmatites, in hydrothermal veins, and as detrital grains in sedimentary rocks.

Uses & applications

Used in electronics, oscillators, glassmaking, abrasives, and as a popular gemstone and ornamental mineral for carving and jewelry.

Geological facts

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

Field identification & locations

Easily identified by its hardness of 7 (it can scratch glass and steel), lack of cleavage, and conchoidal fracture. Found worldwide in nearly every geological setting.