mineral

Quartz (Milky/Clear Quartz)

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Colorless to white/milky; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Colorless to white/milky
Luster: Vitreous (glassy)

Identified July 16, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Colorless to white/milky; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Formed through the cooling of silica-rich magma or from hydrothermal veins. It is one of the most abundant minerals in the Earth's crust and can be found in igneous, metamorphic, and sedimentary environments across all geological ages.

Uses & applications

Used in electronics (as oscillators due to piezoelectricity), glassmaking, abrasives, construction sand, and widely used in jewelry and gemstone collections.

Geological facts

Quartz is chemically and physically very stable at the Earth's surface. Under pressure, it can generate an electric voltage, a property known as piezoelectricity, which is why it is used in watches.

Field identification & locations

Identified in the field by its hardness (it can scratch glass), its lack of cleavage, and its conchoidal (shell-like) fracture. Found globally, especially in granite outcrops, riverbeds, and as veins in mountain ranges.