mineral

Quartz

Silicon Dioxide (SiO2)

Hardness of 7 on the Mohs scale; color varies (commonly white, clear, or gray); 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; color varies (commonly white, clear, or gray); 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, often crystallizing from silica-rich hydrothermal solutions or cooling magma over millions of years

Uses & applications

Used in electronics, watchmaking, glass manufacturing, abrasives, and as a gemstone or specimen for collectors

Geological facts

Quartz is one of the most abundant and widely distributed minerals on Earth's continental crust and exhibits piezoelectric properties, meaning it can generate an electrical charge under mechanical stress

Field identification & locations

Easily identifiable in the field by its high hardness (scratches glass), lack of cleavage, and characteristic conchoidal fracture; found worldwide in almost every geological setting