mineral

Milky Quartz Pebble

Silicon Dioxide (SiO2)

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

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

Identified April 30, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed from the crystallization of silica-rich hydrothermal fluids in veins or as a primary mineral in igneous rocks. This specific specimen has been rounded by fluvial (water) action in a river or beach environment.

Uses & applications

Used conceptually in jewelry as tumbled stones, in landscaping, and industrially for its silica content in glassmaking and electronics.

Geological facts

Milky quartz gets its cloudy white appearance from tiny fluid inclusions of gas or liquid trapped during crystal growth. It is the most common variety of crystalline quartz found on Earth.

Field identification & locations

Identify by its hardness (will scratch glass), lack of cleavage, and white waxy appearance. Commonly found in riverbeds, glacial till, and mountain outcroppings globally.