mineral

Milky Quartz Pebble

Silicon dioxide (SiO2)

Hardness: 7 (Mohs scale), Color: White to off-white with iron staining (orange/brown), Luster: Vitreous to waxy, Crystal structure: Trigonal/Hexagonal, Cleavage: None/Conchoidal fracture, Specific gravity: 2.65

Identified February 19, 2026More mineral →

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Physical properties

Formation & geological history

Formed from cooling magma or hydrothermal veins. This specimen has been rounded by fluvial processes (water erosion), often dated to various geological eras depending on location, typically found in riverbeds or coastal areas.

Uses & applications

Industrial use in glassmaking, abrasives, and electronics. Small polished pebbles are used in landscaping, aquariums, and as pocket stones for collectors.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. The 'milky' appearance is caused by tiny inclusions of gas or liquid trapped during crystal growth.

Field identification & locations

Identified by its hardness (scratches glass), lack of cleavage, and smooth water-worn surface. Commonly found globally in gravel pits, beaches, and stream beds.