mineral

Milky Quartz

Silicon Dioxide (SiO2)

Mohs hardness: 7; Color: White to cloudy or iron-stained orange; Luster: Vitreous to greasy; Crystal Structure: Hexagonal/Trigonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65.

Hardness: 7
Color: White to cloudy or iron-stained orange
Luster: Vitreous to greasy

Identified June 27, 2026More mineral →

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Physical properties

Mohs hardness: 7; Color: White to cloudy or iron-stained orange; Luster: Vitreous to greasy; Crystal Structure: Hexagonal/Trigonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65.

Formation & geological history

Forms primarily in hydrothermal veins and pegmatites through the cooling of silica-rich hot fluids. It is found in a wide range of geological ages from Precambrian to recent, often as the final mineral to crystallize in igneous rocks.

Uses & applications

Used in glass manufacturing, optics, and electronics due to its piezoelectric properties. Used as a flux in metallurgy and commonly as crushed stone for landscaping or road construction. High-quality specimens are used in lapidary work.

Geological facts

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

Field identification & locations

Identify in the field by its hardness (will scratch glass), lack of cleavage, and common occurrence in white veins cutting through other rocks. It is frequently associated with gold in hydrothermal deposit environments.