
mineral
Quartz (specifically Milky Quartz or Quartzite)
Silicon Dioxide (SiO2)
AI-generated identification · may be incorrectHardness: 7 on Mohs scale (scratches glass); Color: White, translucent to milky opaque; Luster: Vitreous (glassy) to greasy; Crystal Structure: Hexagonal (Trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65
- Hardness
- 7 on Mohs scale (scratches glass)
- Color
- White, translucent to milky opaque
- Luster
- Vitreous (glassy) to greasy
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Physical properties
Hardness: 7 on Mohs scale (scratches glass); Color: White, translucent to milky opaque; Luster: Vitreous (glassy) to greasy; Crystal Structure: Hexagonal (Trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65
Formation & geological history
Formed through the cooling of silica-rich magma or through hydrothermal activity in veins. It can also form the bulk of metamorphic quartzite. Native to almost all geological ages due to its stability.
Uses & applications
Used in construction as a component of concrete or road base. In industry, it is a source of silicon for electronics and glass making. Low-grade specimens like this are used for landscaping or aggregate.
Geological facts
Quartz is the second most abundant mineral in Earth's continental crust. It is piezoelectric, meaning it generates an electric charge in response to applied mechanical stress, a property used in watches and radios.
Field identification & locations
Identify by its hardness (it will easily scratch a steel knife blade or glass) and its lack of cleavage (it breaks in irregular, curvy surfaces). Commonly found in gravel pits, riverbeds, and mountain outcrops. Collectors look for well-defined crystal points which this specimen lacks.
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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
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
Septarian Pebble
Septarian nodule / Concretion
sedimentary