mineral

Quartz

Silicon Dioxide (SiO2)

Hardness of 7 on the Mohs scale, typically white, clear, or yellowish due to iron staining, vitreous to greasy luster, trigonal crystal system, conchoidal fracture, specific gravity of 2.65.

Identified August 4, 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, typically white, clear, or yellowish due to iron staining, vitreous to greasy 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 and pegmatites.

Uses & applications

Used in glassmaking, electronics, oscillators, abrasives, gemstones, and ornamental carvings.

Geological facts

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

Field identification & locations

Can be identified by its high hardness (scratches glass), lack of cleavage, and conchoidal fracture. Found worldwide in nearly every type of rock environment.