mineral

Quartz (Milky Quartz)

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: White, translucent to opaque; Luster: Vitreous (glassy) to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: White, translucent to opaque
Luster: Vitreous (glassy) to greasy

Identified March 16, 2026More mineral →

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Physical properties

Formation & geological history

Formed through the cooling of silica-rich magma or from hydrothermal veins. It is one of the most abundant minerals on Earth and can be found in rocks of all geological ages, from Precambrian to modern formations.

Uses & applications

Used in glassmaking, abrasives, foundry sand, and as a source of silicon for electronics. In jewelry, it is used for beads and cabochons. It is also highly valued in the metaphysical and specimen collecting communities.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. 'Milky quartz' gets its white color from tiny fluid inclusions of gas or liquid trapped during crystal growth. It is chemically very stable and resistant to weathering.

Field identification & locations

Identify in the field by its ability to scratch glass, its lack of cleavage (it breaks in curved, shell-like shards), and its waxy or glassy appearance. It is commonly found in gravel, riverbeds, and as veins in larger rock outcroppings globally.