mineral

Milky Quartz

Crystalline 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

Formed in hydrothermal veins or pegmatites from silicon-rich fluids cooling under high pressure. This specimen likely originates from an igneous or metamorphic environment.

Uses & applications

Used primary in glass making, abrasive materials, electronics as a source of high-purity silicon, and as a decorative stone in landscaping or low-cost jewelry.

Geological facts

The milky white color is caused by tiny inclusions of liquid, gas, or both, trapped within the crystal structure during its initial growth. It is the most common variety of crystalline quartz.

Field identification & locations

Identify by its hardness (it will scratch glass), its white opaque color, and lack of true cleavage. It is found globally and is extremely common in mountainous terrain with granite outcrops.