mineral

Quartz Pebble

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: White to milky; Luster: Vitreous/Waxy when polished; Crystal Structure: Trigonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: White to milky
Luster: Vitreous/Waxy when polished

Identified April 4, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: White to milky; Luster: Vitreous/Waxy when polished; Crystal Structure: Trigonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Formed through the cooling of magma or hydrothermal deposition in veins. This specific specimen appears to be a rounded river or beach pebble, shaped by the mechanical weathering and erosion over thousands of years.

Uses & applications

Commonly used in glassmaking, electronics (piezoelectric properties), construction aggregates, and as decorative river stones or pocket stones in landscaping.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. White or 'Milky Quartz' gets its opaque color from tiny fluid inclusions of gas or liquid trapped during crystal growth.

Field identification & locations

Identify in the field by its hardness (it will scratch glass) and lack of cleavage. It is found globally in almost all geological environments and commonly collected in paths, stream beds, and beaches.