mineral

Quartz / Milky Quartz

Silicon Dioxide (SiO2)

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

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

Identified April 7, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed through the cooling of silica-rich magma or from hydrothermal solutions. It is found in igneous, metamorphic, and sedimentary environments across all geological ages.

Uses & applications

Commonly used in glassmaking, abrasives, electronic oscillators (piezoelectricity), construction materials, and as gemstones or decorative carvings.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz gets its white, cloudy appearance from tiny fluid inclusions of gas or liquid trapped during crystal growth.

Field identification & locations

Identify in the field by its ability to scratch glass, its lack of cleavage (breaks like glass), and its glassy luster. It is found globally in pegmatites, veins, and as sand/pebbles in riverbeds.