mineral

Quartz (River Pebble)

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Milky white to tan with iron staining; Luster: Vitreous to waxy (especially when polished or wet); Crystal Structure: Hexagonal/Trigonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Milky white to tan with iron staining
Luster: Vitreous to waxy (especially when polished or wet)

Identified May 26, 2026More mineral →

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Physical properties

Formation & geological history

Formed through the cooling of silica-rich magma or from hydrothermal veins. This specific specimen is a water-worn river pebble, having been tumbled and smoothed by the action of water in a stream or river bed over thousands of years.

Uses & applications

Used in glass making, abrasive manufacturing, electronics (due to piezoelectric properties), and as decorative landscaping stone. Polished versions are used in jewelry and for chakra/reiki practices.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. It is highly resistant to both chemical and physical weathering, which is why it often remains as pebbles after other minerals have eroded away.

Field identification & locations

Identify in the field by its hardness (it should easily scratch glass) and lack of cleavage. Common in riverbeds, beaches, and gravel deposits globally. Look for its translucent nature and smooth, rounded edges in alluvial environments.