mineral
Quartz (Smoky Quartz / Calcite)
SiO2 (Silicon Dioxide)
Hardness: 7 on Mohs scale (if quartz) or 3 (if calcite). Color: Translucent greyish-white to light smoky brown. Luster: Vitreous to greasy. Fracture: Conchoidal to uneven.
- Hardness
- 7 on Mohs scale (if quartz) or 3 (if calcite)
- Color
- Translucent greyish-white to light smoky brown
- Luster
- Vitreous to greasy
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Physical properties
Hardness: 7 on Mohs scale (if quartz) or 3 (if calcite). Color: Translucent greyish-white to light smoky brown. Luster: Vitreous to greasy. Fracture: Conchoidal to uneven.
Formation & geological history
Formed in pegmatites, hydrothermal veins, or sedimentary metamorphic environments through silica-rich or calcium-rich fluid crystallization.
Uses & applications
Used in gemstone collecting, ornamental carvings, jewelry, and industrial applications such as glassmaking and electronics (if quartz).
Geological facts
Smoky quartz receives its subtle grey-brown coloration from natural radiation background interacting with trace aluminum impurities during its formation deep underground.
Field identification & locations
Check hardness with a steel knife (knife scratches calcite, but quartz scratches glass). Look for conchoidal fracture patterns on broken edges. Widely found in granite pegmatites and alpine veins globally.
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