sedimentary
Agate
Silicon Dioxide (SiO2)
AI-generated identification · may be incorrectHardness of 6.5 to 7 on the Mohs scale, waxy to vitreous luster, conchoidal fracture, and typically exhibits banded or mottled colors including pink, white, brown, and red.
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Physical properties
Hardness of 6.5 to 7 on the Mohs scale, waxy to vitreous luster, conchoidal fracture, and typically exhibits banded or mottled colors including pink, white, brown, and red.
Formation & geological history
Formed by the deposition of silica from groundwater in the cavities of igneous and sedimentary rocks over millions of years.
Uses & applications
Widely used in jewelry making, ornamental carvings, decorative objects, and as a popular specimen for rock collectors.
Geological facts
Agate is a microcrystalline variety of quartz, specifically chalcedony, often associated with volcanic environments.
Field identification & locations
Easily identified in the field by its waxy luster, hardness that scratches glass, and distinctive concentric color bands. Found globally, notably in Brazil, the US, and India.
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Sedimentary
Fossiliferous Sedimentary Rock
Sedimentary limestone with invertebrate fossil imprint
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Shale
Fissile Sedimentary Rock
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Sandstone
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