mineral

Milky Quartz

Quartz (Silicon Dioxide - SiO2)

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

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

Identified February 15, 2026More mineral →

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Physical properties

Hardness: 7 (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 milky appearance is caused by tiny inclusions of gas or liquid trapped during crystal growth. Can be found in rocks from almost any geological age.

Uses & applications

Used in glassmaking, abrasives, and as a component in concrete. Low-grade specimens are used in landscaping, while high-quality crystalline clusters are popular with mineral collectors and used in holistic practices.

Geological facts

Milky quartz is the most common variety of crystalline quartz found on Earth. It is often found as the 'gangue' mineral in gold-bearing hydrothermal veins, making it a key indicator for gold prospectors.

Field identification & locations

Identify in the field by its inability to be scratched by a steel knife (hardness 7) and its lack of cleavage planes. Found globally in mountainous regions, riverbeds, and as veins in metamorphic or igneous rock.