mineral

Quartz (Crystal)

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Clear to translucent milky white; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: Indistinct/conchoidal fracture; Specific gravity: 2.65

Hardness: 7 on Mohs scale
Color: Clear to translucent milky white
Luster: Vitreous (glassy)

Identified July 20, 2026More mineral →

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Physical properties

Formation & geological history

Forms in a wide variety of environments, most commonly from the cooling of magma or by hydrothermal precipitation in veins. It is found in igneous, metamorphic, and sedimentary rocks of all ages.

Uses & applications

Extensively used in electronics (oscillators), glassmaking, abrasives, jewelry (as a gemstone), and as a component in construction materials like concrete and mortar.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. It is piezoelectric, meaning it generates an electric charge in response to applied mechanical stress, which is why it is used in watches.

Field identification & locations

Identify in the field by its hardness (it scratches glass), glassy luster, and shell-like (conchoidal) fracture. Found globally, especially in mountain ranges and riverbeds. Look for hexagonal points in undisturbed cavities.