mineral

Quartz (Milky Quartz)

Silicon Dioxide (SiO2)

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

Hardness: 7 on Mohs scale
Color: White to creamy/milky
Luster: Vitreous to greasy

Identified May 4, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed from the cooling of silica-rich magma or through hydrothermal veins where mineral-saturated hot water deposits crystals in rock fractures. Common in almost all geological ages and environments.

Uses & applications

Used in glass manufacturing, electronics (due to piezoelectric properties), abrasives, jewelry (as semi-precious gemstones), and as a decorative landscaping stone.

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.

Field identification & locations

Identify in the field by its ability to scratch glass and steel, its white/waxy appearance, and lack of cleavage. Often found on beaches and in riverbeds as rounded 'water-worn' pebbles.