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 with variable colors ranging from grey to blue.
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Physical properties
Hardness of 6.5 to 7 on the Mohs scale, waxy luster, and cryptocrystalline structure with variable colors ranging from grey to blue.
Formation & geological history
Forms in low-temperature hydrothermal environments and cavities of volcanic rocks through the deposition of silica-rich groundwater.
Uses & applications
Widely used for ornamental carvings, gemstones, jewelry, and lapidary art.
Geological facts
Ancient civilizations prized chalcedony for intricately carved signet rings and amulets.
Field identification & locations
Identify by its waxy luster, conchoidal fracture, and lack of visible crystal grains. Found globally in volcanic regions and river gravels.
