mineral

Quartz

Silicon Dioxide (SiO2)

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

Identified July 31, 2026More mineral →

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Physical properties

Hardness of 7 on the Mohs scale, clear to yellowish-white color, vitreous to greasy 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 crystallizes from silica-rich hydrothermal solutions and magma, and is extremely resistant to weathering.

Uses & applications

Used in electronics (oscillators), manufacturing of glass, ceramics, abrasives, and as gemstones or collector minerals.

Geological facts

Quartz is one of the most abundant and widely distributed minerals on Earth's continental crust. Its piezoelectric properties make it essential in modern timekeeping devices and electronics.

Field identification & locations

Easily identified by its hardness (scratches glass), conchoidal fracture, and lack of cleavage. Found worldwide in almost every rock type, especially in pegmatites, veins, and quartzites.