mineral
River Quartz Cobble
Silicon Dioxide (SiO2)
AI-generated identification · may be incorrectHardness: 7 on Mohs scale; Color: Tan, white, and smoky brown; Luster: Vitreous to waxy (weathered); Crystal Structure: Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65
- Hardness
- 7 on Mohs scale
- Color
- Tan, white, and smoky brown
- Luster
- Vitreous to waxy (weathered)
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Physical properties
Hardness: 7 on Mohs scale; Color: Tan, white, and smoky brown; Luster: Vitreous to waxy (weathered); Crystal Structure: Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65
Formation & geological history
Formed through hydrothermal processes or igneous crystallization and later eroded and polished by water action in a river or stream environment over thousands of years.
Uses & applications
Primarily decorative in landscaping, used as an abrasive in industrial sandblasting, or as a source of silica for glass manufacturing.
Geological facts
Quartz is the second most abundant mineral in Earth's continental crust. This specific specimen shows 'chatter marks' and rounding typical of fluvial transportation.
Field identification & locations
Identify by its ability to scratch glass and lack of reaction to acid. Commonly found in riverbeds, glacial tills, and beaches globally.
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Other mineral specimens
Gneiss or Schist
Gneiss or Mica Schist with Garnet
Metamorphic
Sandstone (with potential mineral staining/concretions)
Arenite (SiO2 based)
sedimentary
Tumbled granite
Granite, a coarse-grained felsic intrusive igneous rock
igneous
Epidote
Epidote | Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH)
metamorphic
Pegmatite with Tourmaline and Quartz
Igneous Pegmatite
igneous
Granite
Granite (Phaneritic intrusive igneous rock)
igneous