mineral

Quartz (Microcrystalline Gravel)

Silicon Dioxide (SiO2)

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

Hardness: 7 (Mohs scale)
Color: Grayish-white/translucent
Luster: Vitreous to waxy

Identified May 26, 2026More mineral →

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Physical properties

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

Formation & geological history

Forms in a wide variety of environments, primarily through the cooling of silica-rich magma or precipitation from hydrothermal veins. This specific specimen appears to be a weathered fragment of vein quartz.

Uses & applications

Used extensively in glass making, electronics (piezoelectric properties), abrasives, and as a primary component in concrete and construction gravel.

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 persists as small pebbles in soil and sand.

Field identification & locations

Identify by its hardness (will scratch glass) and lack of cleavage. Commonly found in riverbeds, garden soil, and construction sites worldwide as aggregate.

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