mineral

Quartz (Milky Quartz)

Silicon Dioxide (SiO2)

Hardness: 7 (Mohs scale); Color: White to translucent; Luster: Vitreous (glassy) to greasy; Crystal structure: Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Hardness: 7 (Mohs scale)
Color: White to translucent
Luster: Vitreous (glassy) to greasy

Identified April 7, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale); Color: White to translucent; Luster: Vitreous (glassy) to greasy; Crystal structure: Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Formation & geological history

Formed through the cooling of silica-rich magma or from hydrothermal veins. It is found in all geological environments and can be from any geological age, though major veins often form during orogenic (mountain-building) events.

Uses & applications

Used in glassmaking, as an abrasive in sandblasting, in the manufacturing of semiconductors and electronics due to its piezoelectric properties, and as a semi-precious gemstone/ornamental stone.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz gets its characteristic white color from microscopic fluid inclusions of gas or liquid trapped during crystal growth.

Field identification & locations

Identify in the field by its hardness (cannot be scratched by steel), glassy luster on fresh surfaces, and lack of cleavage (it breaks in irregular or shell-like curves). It is found worldwide in mountain ranges, rivers, and pegmatites.