mineral

Quartz

Silicon Dioxide (SiO2)

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

Identified July 28, 2026More mineral →

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Physical properties

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

Formation & geological history

Forms in a wide variety of geological environments, commonly crystallizing from silica-rich hydrothermal veins and magmatic pegmatites, as well as being a primary constituent of many igneous, metamorphic, and sedimentary rocks.

Uses & applications

Used in electronics, oscillators, glassmaking, abrasives, gemstone carvings, and as a mineral specimen for collectors.

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 when compressed.

Field identification & locations

Easily identified by its characteristic 7 Mohs hardness (can scratch glass) and conchoidal fracture. Found globally, with notable deposits in Brazil, the United States, Madagascar, and the Alps.