mineral

Milky 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 May 17, 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

Forms through the crystallization of silica-rich magma or precipitation from hydrothermal veins. The milky appearance is caused by tiny inclusions of gas or liquid trapped during crystal growth.

Uses & applications

Used in glassmaking, abrasives, electronic components (due to piezoelectricity), and as ornamental stones or landscaping material.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz specifically gets its appearance from 'optical scattering' caused by microscopic fluid inclusions.

Field identification & locations

Identified in the field by its hardness (scratches glass), lack of cleavage, and waxy luster. Common in mountain ranges and riverbeds globally. It is an indicator mineral for potential gold veins in hydrothermal settings.