mineral

Quartz

Silicon Dioxide (SiO2)

Hardness of 7 on the Mohs scale, typically white, clear, or milky in color, vitreous to greasy 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, typically white, clear, or milky in color, vitreous to greasy 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 solutions or cooling magma over millions of years.

Uses & applications

Used in electronics for oscillators, glass manufacturing, abrasives, gemstones, and decorative items.

Geological facts

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

Field identification & locations

Easily identified by its high hardness (scratches glass), lack of cleavage, and conchoidal fracture. Found worldwide in beaches, rivers, and vein deposits.