mineral

Quartz

Silicon Dioxide (SiO2)

Hardness of 7 on the Mohs scale, transparent to translucent, vitreous luster, trigonal crystal system, conchoidal fracture with no true cleavage, specific gravity of 2.65.

Identified August 5, 2026More mineral →

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Physical properties

Hardness of 7 on the Mohs scale, transparent to translucent, vitreous 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. It is a common constituent of pegmatites, hydrothermal veins, and sandstones.

Uses & applications

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

Geological facts

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

Field identification & locations

Easily identified by its high hardness (scratches glass), lack of cleavage, and characteristic conchoidal fracture. Found worldwide in almost every geological setting.