Rock Identifier
Chalcedony (Silicon Dioxide (SiO2)) — mineral
mineral

Chalcedony

Silicon Dioxide (SiO2)

AI-generated identification · may be incorrect

Hardness of 6.5 to 7 on the Mohs scale, waxy luster, and cryptocrystalline structure with variable colors including blue, gray, and white.

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Physical properties

Hardness of 6.5 to 7 on the Mohs scale, waxy luster, and cryptocrystalline structure with variable colors including blue, gray, and white.

Formation & geological history

Forms in low-temperature hydrothermal environments, often filling cavities in volcanic and sedimentary rocks.

Uses & applications

Used extensively for ornamental carvings, gemstones, and lapidary art.

Geological facts

Chalcedony is a microfibrous variety of quartz that includes famous sub-varieties like agate and jasper.

Field identification & locations

Identified by its waxy luster and conchoidal fracture, commonly found worldwide in volcanic rock cavities.