mineral

Quartz

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale, Color: Colorless, white, gray, brown, or smoky, Luster: Vitreous (glassy), Crystal structure: Trigonal, Cleavage: None (conchoidal fracture), Specific gravity: 2.65

Identified August 2, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale, Color: Colorless, white, gray, brown, or smoky, Luster: Vitreous (glassy), Crystal structure: Trigonal, Cleavage: None (conchoidal fracture), Specific gravity: 2.65

Formation & geological history

Forms in a wide variety of geological environments, including igneous, metamorphic, and sedimentary rocks. It is a primary component of granite and pegmatites, and precipitates from hydrothermal solutions.

Uses & applications

Used in electronics, glassware, precision instruments, gemstones, and abrasives.

Geological facts

Quartz is one of the most abundant minerals in Earth's continental crust and exhibits piezoelectric properties, meaning it can generate an electric charge under mechanical stress.

Field identification & locations

Easily identified by its conchoidal fracture, lack of cleavage, and high hardness (scratches glass). Found worldwide in almost all types of rock formations.