mineral

Quartz / Milky Quartz

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 February 18, 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

Forms from cooling magma or in hydrothermal veins under varying temperatures and pressures. It exists in almost all geological ages and environments, from igneous rocks like granite to sedimentary sandstones and metamorphic quartzites.

Uses & applications

Used in glass manufacturing, electronics (due to piezoelectric properties), abrasives, construction sand, and as a popular semi-precious gemstone in jewelry and metaphysical collections.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Pure quartz is known as rock crystal, while the milky appearance in specimens like this is caused by tiny inclusions of liquid or gas trapped during crystal growth.

Field identification & locations

Identify in the field by its hardness (it can scratch glass), lack of cleavage, and glassy appearance. It is found globally across all continents. Collectors look for well-defined hexagonal crystal points or unique clarity.

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