Mineral

Quartz Pebble

Silicon Dioxide (SiO2)

Hardness: 7 on the Mohs scale; Color: White to translucent; Luster: Vitreous to waxy; Crystal Structure: Trigonal/Hexagonal (though massive/rounded here); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on the Mohs scale
Color: White to translucent
Luster: Vitreous to waxy

Identified March 21, 2026More mineral →

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Physical properties

Formation & geological history

Formed from the cooling of silica-rich magma or through hydrothermal veins. This specific specimen is weather-worn, meaning it has been mechanically eroded by water (river or beach action) over thousands of years.

Uses & applications

Used in glassmaking, electronics (piezoelectric properties), and construction. River-worn pebbles are popular in landscaping and as 'worry stones' for collectors.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Its name comes from the Greek word 'krystallos', meaning ice, as ancient Greeks believed quartz was ice that had frozen so hard it would never melt.

Field identification & locations

Identify by its ability to scratch glass and its lack of cleavage. Common in riverbeds and on beaches globally. For collectors, look for smoothness and translucency.