mineral

Quartz

Silicon Dioxide (SiO2)

Hardness of 7 on the Mohs scale, clear to white or milky color, vitreous luster, hexagonal crystal system, no true cleavage with conchoidal fracture, specific gravity of 2.65.

Identified August 4, 2026More mineral →

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Physical properties

Hardness of 7 on the Mohs scale, clear to white or milky color, vitreous luster, hexagonal crystal system, no true cleavage with conchoidal fracture, specific gravity of 2.65.

Formation & geological history

Forms in a wide variety of geological environments, including igneous, metamorphic, and sedimentary rocks. It is a common component of pegmatites and hydrothermal veins.

Uses & applications

Used in electronics, oscillators, glassmaking, abrasives, and as a gemstone or ornamental stone in 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 under mechanical stress.

Field identification & locations

Identified by its high hardness (scratches glass), conchoidal fracture, and lack of reactivity to acids. Found worldwide in nearly every type of rock environment.