mineral

Quartz (Gravel fragment)

Quartz (Silicon Dioxide, SiO2)

Hardness: 7 (Mohs scale); Color: Creamy white to translucent; Luster: Vitreous to waxy (when weathered); Crystal Structure: Hexagonal (trigonal); Cleavage: Indistinct/Conchoidal fracture; Specific gravity: 2.65

Hardness: 7 (Mohs scale)
Color: Creamy white to translucent
Luster: Vitreous to waxy (when weathered)

Identified March 20, 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 fragment appears to be a water-worn or mechanically weathered piece of 'pea gravel' likely dating from various geological eras depending on its parent rock.

Uses & applications

Common quartz is used extensively in construction (aggregate), glassmaking, abrasives, and as a component in concrete. Small pebbles are often used in landscaping.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. It is chemically and physically resistant to weathering, which is why it often remains as small pebbles while other minerals dissolve.

Field identification & locations

Identify in the field by its hardness (it will scratch glass) and lack of reaction to acid. It is found globally in riverbeds, beaches, and soil. For collectors, small unpatterned fragments are common 'filler' stones.

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