mineral

Quartz Pebble

Silicon Dioxide (SiO2)

Hardness: 7 (Mohs scale); Color: Milky white to translucent; Luster: Vitreous/waxy; Crystal Structure: Trigonal; Cleavage: None/Conchoidal fracture; Specific gravity: 2.65

Hardness: 7 (Mohs scale)
Color: Milky white to translucent
Luster: Vitreous/waxy

Identified June 3, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale); Color: Milky white to translucent; Luster: Vitreous/waxy; Crystal Structure: Trigonal; Cleavage: None/Conchoidal fracture; Specific gravity: 2.65

Formation & geological history

Formed from molten magma as it cools or from hydrothermal veins. This specific specimen has been rounded and smoothed by mechanical weathering, likely through river or ocean wave action.

Uses & applications

Used in decorative landscaping, glass manufacturing, abrasives, and as semi-precious stones in jewelry or as 'pocket stones' for collectors.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. When found as smooth pebbles like this, they are often called 'river stones' or 'beach quartz'.

Field identification & locations

Identifiable in the field by its hardness (it can scratch glass), lack of cleavage, and smooth, rounded surface resulting from water erosion. Found worldwide in stream beds, beaches, and glacial deposits.