mineral

Quartz (Field Stone)

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Grayish-white to clear with some iron staining; Luster: Vitreous to waxy (weathered); Crystal structure: Hexagonal/Trigonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Grayish-white to clear with some iron staining
Luster: Vitreous to waxy (weathered)

Identified July 15, 2026More mineral →

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Physical properties

Formation & geological history

Formed from silica-rich hydrothermal fluids or within igneous and metamorphic environments. This specimen appears water-worn or weathered, suggesting it was found in a secondary deposit like a riverbed or glacial till.

Uses & applications

Mainly used in industrial glass manufacturing, electronics, and as an abrasive. Specimens like this are primarily of interest to amateur collectors as garden stones or keepsakes.

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 survives as pebbles long after other minerals have decomposed.

Field identification & locations

Identify in the field by its hardness (it will scratch glass and stainless steel) and its lack of cleavage. It is commonly found worldwide in gravel pits, beaches, and mountain streams.