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 June 24, 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 late-stage mineral in igneous pegmatites. The milky appearance is caused by tiny fluid or gas inclusions trapped during crystal growth.

Uses & applications

Used as a source of silicon for electronics, in glassmaking, as an abrasive, in construction as aggregate, and frequently in landscaping or as a collector's specimen.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz specifically can host inclusions of gold in certain geological gold-bearing veins.

Field identification & locations

Identified by its white color, ability to scratch glass (hardness 7), and lack of cleavage planes. It is commonly found in riverbeds, mountain ranges, and as vein material in many rock types worldwide.