mineral

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

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

Hardness: 7 on Mohs scale
Color: Opaque white to translucent
Luster: Vitreous to greasy

Identified February 22, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed through the cooling and crystallization of silica-rich magma or from hydrothermal veins. The white 'milky' appearance is caused by tiny inclusions of gas or liquid trapped during the crystal's growth. It can be found in almost all geological environments and ages.

Uses & applications

Used in the manufacturing of glass and ceramics, as an abrasive in sandpaper, in high-accuracy watches (piezoelectric properties), and as decorative gravel or crushed stone in construction. Polished pieces are used in costume jewelry and as 'healing' stones in metaphysical shops.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz specifically is white because of microscopic 'fluid inclusions'—bubbles of water or gas—that scatter light. It is often found associated with gold in hydrothermal vein deposits.

Field identification & locations

Identify in the field by its hardness (it will scratch glass and steel), lack of cleavage, and translucent white color. It is extremely common in riverbeds as rounded 'river rocks' due to its high durability and resistance to weathering.