mineral

Milky Quartz

Silicon Dioxide (SiO2)

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

Hardness: 7 on Mohs scale
Color: Milky white to opaque
Luster: Vitreous to greasy

Identified May 5, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed through the crystallization of silica-rich hydrothermal fluids in veins or as a primary constituent in igneous rocks like granite. The milky appearance is caused by microscopic fluid inclusions of gas or liquid trapped during crystal growth.

Uses & applications

Used in glass manufacturing, as an abrasive, in electronics (due to piezoelectric properties), construction aggregate, and in landscaping or as a lapidary material for jewelry like cabochons.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz is often associated with gold deposits in quartz veins, making it a key indicator for prospectors.

Field identification & locations

Identify in the field by its hardness (it will scratch glass), lack of cleavage, and white color. It is found globally in almost all geological environments, especially in mountain ranges and gravel beds.