mineral

Quartz Pebble

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale. Color: Translucent white to milky gray. Luster: Vitreous (glassy) to waxy when water-worn. Crystal Structure: Hexagonal (trigonal). Cleavage: None (conchoidal fracture). Specific Gravity: 2.65.

Hardness: 7 on Mohs scale
Color: Translucent white to milky gray
Luster: Vitreous (glassy) to waxy when water-worn

Identified April 6, 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 is a 'river rock' or 'tumble-worn' pebble, shaped by millions of years of water erosion in a riverbed or coastal environment.

Uses & applications

Used in construction, glass manufacturing, electronics (due to piezoelectric properties), and as a gemstone or decorative landscape stone. Tumbled stones are popular for 'pocket stones' or crystal healing collections.

Geological facts

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

Field identification & locations

Identify in the field by its hardness (it can scratch glass and steel) and lack of cleavage. Found globally in riverbeds, beaches, and gravel deposits. Look for translucency and 'moon-like' internal fractures.