mineral

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

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

Hardness: 7 on Mohs scale
Color: Cloudy white to opaque
Luster: Vitreous (glassy) to greasy

Identified March 7, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Cloudy white to opaque; Luster: Vitreous (glassy) 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 geological formations of all ages.

Uses & applications

Used in the glass-making industry, as an abrasive, in the production of silicon chips for electronics, and as decorative stone or gravel in landscaping. Quality specimens are used in jewelry and lapidary art.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz is the most common variety of crystalline quartz found in nature. Historically, it has been used for stone tools when flint was unavailable.

Field identification & locations

Identify in the field by its hardness (it will easily scratch glass), its white cloudy appearance, and its lack of cleavage (it breaks in curved, shell-like patterns). Commonly found in pegmatites, hydrothermal veins, and as cobbles in riverbeds.