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

Purple Chalcedony

Silicon Dioxide (SiO2)

Hardness of 6.5 to 7 on the Mohs scale, waxy to vitreous luster, cryptocrystalline structure, conchoidal fracture, specific gravity of 2.58 to 2.64.

Identified More mineral
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Physical properties

Hardness of 6.5 to 7 on the Mohs scale, waxy to vitreous luster, cryptocrystalline structure, conchoidal fracture, specific gravity of 2.58 to 2.64.

Formation & geological history

Formed in low-temperature hydrothermal environments or as deposits from silica-rich solutions filling cavities in host rocks, often associated with volcanic activity.

Uses & applications

Used in gemstone carving, lapidary arts, decorative items, and mineral collecting.

Geological facts

Chalcedony has been used for thousands of years by various ancient civilizations to create intaglios, seals, and ornamental jewelry.

Field identification & locations

Identified by its waxy luster, microcrystalline nature, and characteristic purple color variations. Found worldwide in volcanic and sedimentary rock cavities.