mineral

Milky Quartz Pebble

Silicon Dioxide (SiO2)

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

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

Identified June 10, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed via hydrothermal activity where silica-rich fluids cool in veins, or within igneous rocks like granite. This specimen is water-worn, smoothed by erosion in a river or beach environment.

Uses & applications

Used in glassmaking, electronics (piezoelectric properties), abrasives, and as decorative landscaping stone. High-purity quartz is used in semiconductor manufacturing.

Geological facts

The milky white color is caused by tiny inclusions of gas or liquid trapped during the crystal's growth. It is the most common variety of crystalline quartz.

Field identification & locations

Identify by its white color, ability to scratch glass, and lack of cleavage. Often found in riverbeds, glacial tills, and mountainous regions worldwide.