mineral

Rough Quartz (or Quartzite pebble)

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Colorless to milky white/light grey; Luster: Vitreous to greasy; Crystal structure: Trigonal/Hexagonal (though water-worn in this specimen); Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Hardness: 7 on Mohs scale
Color: Colorless to milky white/light grey
Luster: Vitreous to greasy

Identified March 1, 2026More mineral →

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Physical properties

Formation & geological history

Formed through the crystallization of silica-rich magma or through hydrothermal activity in veins. It is also found in sedimentary environments as a result of the erosion of primary igneous rocks. This specimen appears water-worn, suggesting a fluvial or beach origin.

Uses & applications

Quartz is used in the manufacture of glass, ceramics, and electronics (due to piezoelectric properties). In this rough form, it is primarily used in construction aggregate, landscaping, or as a pocket stone for collectors.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Pure quartz is traditionally called rock crystal or clear quartz. It is extremely resistant to chemical and physical weathering, which is why it often survives as rounded pebbles in riverbeds.

Field identification & locations

Identify in the field by its inability to be scratched by a steel knife (hardness 7) and its lack of visible cleavage planes. It is found globally in almost all geological environments. Collectors look for clarity and crystal terminations, though this piece is a common tumble-worn specimen.

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