sedimentary
Agate
Silicon dioxide (chalcedony), SiO2
AI-generated identification · may be incorrectHardness of 6.5-7 on the Mohs scale, waxy luster, and microcrystalline trigonal structure with distinctive banded color patterns.
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Physical properties
Hardness of 6.5-7 on the Mohs scale, waxy luster, and microcrystalline trigonal structure with distinctive banded color patterns.
Formation & geological history
Forms by the deposition of silica from groundwater in cavities of igneous and sedimentary rocks over millions of years.
Uses & applications
Widely used in ornamental carvings, jewelry, decorative items, and precision laboratory instruments.
Geological facts
Agate is one of the oldest known talismanic stones, prized by ancient civilizations for its protective and healing properties.
Field identification & locations
Identified by its signature concentric color banding and conchoidal fracture; commonly found globally in volcanic rock cavities.
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Sandstone or Siltstone
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