mineral

Milky Quartz Pebble

Quartz (Silicon Dioxide, SiO2)

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

Hardness: 7 (Mohs scale)
Color: White to creamy tan/translucent
Luster: Vitreous to greasy

Identified June 24, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed from hydrothermal solutions or igneous crystallization, then weathered and transported by water into a rounded river stone. Frequently found in allochthonous deposits.

Uses & applications

Used for lapidary tumbling, aggregate in construction, and as a source of silica for glass and electronics when found in high purity.

Geological facts

Milky quartz gets its cloudy appearance from tiny fluid inclusions of gas and/or liquid trapped during the crystal's growth. It is the most common variety of crystalline quartz.

Field identification & locations

Identified by its ability to scratch glass (Hardness 7) and its smooth, waxy surface when wet. Commonly found in riverbeds, beaches, and glacial till globally.