mineral

Quartz (River Pebble)

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Milky white to translucent tan with pink/red hematite staining; Luster: Vitreous to waxy (when water-worn); Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); SG: 2.65

Hardness: 7 on Mohs scale
Luster: Vitreous to waxy (when water-worn)

Identified July 14, 2026More mineral →

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Physical properties

Formation & geological history

Formed from silica-rich hydrothermal fluids or within igneous and metamorphic rocks. This specific specimen has been Rounded and smoothed by fluvial or glacial transport over thousands of years.

Uses & applications

River quartz is used in landscaping, as a construction aggregate, and occasionally tumbled for lapidary hobbies. Crystalline quartz is essential for making glass, ceramics, and electronics (due to piezoelectricity).

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. The faint pink/orange tint in this specimen is likely caused by trace amounts of iron oxide (hematite) leeching into micro-fractures in the stone.

Field identification & locations

Identified by its ability to scratch glass, lack of cleavage, and smooth, rounded surface. Found globally in riverbeds, beaches, and glacial till. Collectors can find these easily in almost any waterway.