mineral

Milky Quartz

Quartz (Silicon Dioxide - SiO2)

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

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

Identified March 23, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed through the cooling of silica-rich magma or from hydrothermal veins. The white 'milky' appearance is caused by minute fluid inclusions of gas and/or liquid trapped during crystal growth. Can be found in rocks of almost any geological age.

Uses & applications

Used in the glassmaking and ceramic industries, as an abrasive, in the production of silicon metal, and for landscaping or interior decor. Frequently collected by rockhounds as a fundamental mineral specimen.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Ancient Greeks named the mineral 'krustallos' (ice), believing it to be water frozen so hard it would never melt. Milky quartz is the most common variety of quartz.

Field identification & locations

Identify in the field by its hardness (will scratch glass and steel), white color, and lack of cleavage. It is found globally in pegmatites, hydrothermal veins, and as pebbles in riverbeds or on beaches.