mineral

Milky Quartz

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: White to grey, sometimes iron-stained brown/yellow; Luster: Vitreous to greasy; Crystal Structure: Trigonal (hexagonal system); Cleavage: None/Conchoidal fracture; Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: White to grey, sometimes iron-stained brown/yellow
Luster: Vitreous to greasy

Identified June 13, 2026More mineral →

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Physical properties

Formation & geological history

Forms in hydrothermal veins or as a constituent of igneous rocks through the cooling of silica-rich magma or precipitation from hot fluids in the Earth's crust. Commonly found in precambrian to recent geological formations.

Uses & applications

Used in glass making, abrasive manufacturing, electronics, and occasionally as a base material for inexpensive jewelry or lapidary work. It is a major component of concrete and mortar in its crushed form.

Geological facts

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

Field identification & locations

Identify by its characteristic hardness (will scratch glass), lack of cleavage, and waxy to vitreous luster. Commonly found in river beds, mountainous regions, and garden landscaping across the globe.