mineral

Quartz (Microcrystalline/Gravel)

Silicon Dioxide (SiO2)

Hardness: 7 (Mohs scale); Color: White to semi-translucent; Luster: Vitreous to waxy; Crystal structure: Hexagonal/Trigonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Hardness: 7 (Mohs scale)
Color: White to semi-translucent
Luster: Vitreous to waxy

Identified June 2, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale); Color: White to semi-translucent; Luster: Vitreous to waxy; Crystal structure: Hexagonal/Trigonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Formation & geological history

Formed through crystallization of igneous melt or hydrothermal precipitation. This specimen appears to be a weathered or water-worn fragment potentially from a sedimentary gravel deposit.

Uses & applications

Used widely in glassmaking, electronics (piezoelectric properties), abrasives, construction aggregates, and as gemstones in different varieties.

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 small pebbles after other minerals have eroded.

Field identification & locations

Identify in the field by its hardness (will scratch glass), lack of cleavage, and resistance to acids. Commonly found in riverbeds, beaches, and as veins in virtually all rock types.

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Mineral/Rock

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