mineral

Milky Quartz

Silicon Dioxide (SiO2)

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

Hardness: 7 on Mohs scale
Color: Opaque white to translucent
Luster: Vitreous to greasy

Identified July 7, 2026More mineral →

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Physical properties

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

Formation & geological history

Forms from the crystallization of silicon dioxide in hydrothermal veins and pegmatites. The milky white color is caused by microscopic fluid inclusions of gas or liquid trapped during crystal growth.

Uses & applications

Used in landscaping, construction aggregate, glass making, electronics (piezoelectric properties), and as a semi-precious gemstone in jewelry.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz is specifically opaque because of many tiny bubbles within the mineral. It is often found associated with gold in hydrothermal vein deposits.

Field identification & locations

Identify by its white color, hardness (it will scratch glass), and lack of cleavage. It is found globally and is common in mountain ranges and riverbeds. For collectors, look for well-defined hexagonal crystal faces.