mineral

Milky Quartz

Quartz (Silicon Dioxide - SiO2)

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

Identified May 22, 2026More mineral →

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Physical properties

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

Formation & geological history

Forms primarily from the cooling of silica-rich hydrothermal fluids in veins or pegmatites. The milky appearance is caused by microscopic inclusions of gas or liquid trapped during crystal growth.

Uses & applications

Used in glass manufacturing, electronics (piezoelectric properties), abrasives, and as decorative stone in landscaping or jewelry (cabochons).

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Historically, it was used to produce stone tools. Milky quartz is the most common variety of quartz.

Field identification & locations

Identify in the field by its hardness (will scratch glass but not be scratched by steel), lack of cleavage, and white soapy or vitreous appearance. Commonly found in quartz veins and as pebbles in riverbeds worldwide.