mineral

Quartz (Milky Quartz)

Silicon Dioxide (SiO2)

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

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

Identified June 12, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; 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 cooling of magma or by precipitation from hydrothermal veins. This specimen likely originated from a vein where fluid inclusions gave it a milky appearance.

Uses & applications

Used in glassmaking, abrasives, electronics (due to piezoelectric properties), and as a gemstone or specimen for collectors.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz gets its opaque white color from tiny bubbles of gas or liquid trapped during crystal growth.

Field identification & locations

Identify in the field by its hardness (it can scratch glass), lack of cleavage, and white color. Very common globally in mountainous and riverbed environments.