mineral

Quartz

Silicon Dioxide (SiO2)

Hardness of 7 on the Mohs scale, colorless to various colors depending on impurities, vitreous luster, trigonal crystal system, conchoidal fracture, specific gravity of 2.65.

Identified August 1, 2026More mineral →

Explore Quartz in the encyclopedia →

Identify your own rocks.

Get a report just like this from any photo, free.

App Store Google Play

Physical properties

Hardness of 7 on the Mohs scale, colorless to various colors depending on impurities, vitreous luster, trigonal crystal system, conchoidal fracture, 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 or magma.

Uses & applications

Used in electronics, oscillators, glassmaking, abrasives, and as gemstones or decorative specimens in jewelry.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust, surpassed only by feldspar. It exhibits piezoelectric properties, meaning it can generate an electrical charge in response to mechanical stress.

Field identification & locations

Identified by its high hardness (scratches glass), conchoidal fracture, and lack of cleavage. Found worldwide in nearly every type of geological terrain.