mineral
Chalcedony
Silicon Dioxide (SiO2)
AI-generated identification · may be incorrectHardness of 6.5 to 7 on the Mohs scale, waxy luster, and cryptocrystalline structure. Color ranges from white and grey to blue and brown.
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Physical properties
Hardness of 6.5 to 7 on the Mohs scale, waxy luster, and cryptocrystalline structure. Color ranges from white and grey to blue and brown.
Formation & geological history
Forms in low-temperature hydrothermal environments and by deposition from silica-rich groundwater within rock cavities.
Uses & applications
Used widely in ornamental carvings, gemstone jewelry, and decorative objects. Highly valued by mineral collectors.
Geological facts
Chalcedony is the microcrystalline parent material for many well-known gemstones including agate, jasper, and onyx. Ancient civilizations carved it into cylinder seals and intaglios.
Field identification & locations
Identified by its waxy luster, conchoidal fracture, and lack of visible crystal faces. Commonly found worldwide in volcanic and sedimentary rock cavities.
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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
Pegmatite with Tourmaline and Quartz
Igneous Pegmatite
igneous
Epidote
Epidote | Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH)
metamorphic
Granite
Granite (Phaneritic intrusive igneous rock)
igneous