mineral

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Hardness: 7 (Mohs scale); Color: White to off-white/translucent; Luster: Vitreous to greasy; Crystal Structure: Trigonal (hexagonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65.

Hardness: 7 (Mohs scale)
Color: White to off-white/translucent
Luster: Vitreous to greasy

Identified February 5, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale); Color: White to off-white/translucent; Luster: Vitreous to greasy; Crystal Structure: Trigonal (hexagonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65.

Formation & geological history

Formed in hydrothermal veins and pegmatites through the cooling of silica-rich fluids. It occurs in nearly all geological environments and can be millions to billions of years old depending on the host rock formation.

Uses & applications

Used in glass making, ceramics, abrasives, and as a component in concrete and mortar. Higher quality specimens are used for beads, carvings, and decorative landscaping.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Its milky appearance is caused by tiny inclusions of gas and liquids trapped during the crystal's growth.

Field identification & locations

Identified in the field by its ability to scratch glass, its lack of cleavage, and its waxy or vitreous luster. It is found globally, common in riverbeds and mountainous terrain. Collectors should look for distinct crystalline faces.