mineral

Quartz (Milky Quartz)

Silicon Dioxide (SiO2)

Hardness: 7.0 Mohs; Color: White to opaque; Luster: Vitreous to greasy; Crystal Structure: Hexagonal/Trigonal; Cleavage: None/Conchoidal fracture; Specific Gravity: 2.65

Hardness: 7
Color: White to opaque
Luster: Vitreous to greasy

Identified June 2, 2026More mineral →

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Physical properties

Hardness: 7.0 Mohs; Color: White to opaque; Luster: Vitreous to greasy; Crystal Structure: Hexagonal/Trigonal; Cleavage: None/Conchoidal fracture; Specific Gravity: 2.65

Formation & geological history

Formed through the crystallization of silica-rich magma or from hydrothermal veins. It is found in almost all geological environments and across all geological ages, from Precambrian to the present.

Uses & applications

Used in glassmaking, electronics (piezoelectric properties), abrasives, construction as an aggregate, and widely collected as mineral specimens or used in jewelry.

Geological facts

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

Field identification & locations

Identify in the field by its hardness (cannot be scratched by a steel knife), lack of cleavage, and white streak. It is found worldwide, common in mountain ranges and river gravels.