mineral

Quartz

Silicon Dioxide (SiO2)

Hardness of 7 on the Mohs scale, color ranges from clear to white, grey, or yellowish/brownish due to impurities. Vitreous (glassy) luster, trigonal crystal system, conchoidal fracture with no true cleavage, and a specific gravity of 2.65.

Identified August 4, 2026More mineral →

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Physical properties

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 over millions of years.

Uses & applications

Used widely in electronics (oscillator crystals), glassmaking, abrasives, construction aggregates, and as gemstones or ornamental specimens in jewelry and crystal collecting.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust, surpassed only by feldspar. Its piezoelectric properties allow it to generate an electrical charge under mechanical stress, making it essential for accurate timekeeping in watches.

Field identification & locations

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