mineral

Chalcedony (Agate/Carnelian variant)

Silicon Dioxide (SiO2)

Hardness: 6.5-7 (Mohs scale), Color: Pale orange to waxy translucent yellow, Luster: Waxy to vitreous, Crystal structure: Microcrystalline (trigonal), Cleavage: None/Conchoidal fracture, Specific gravity: 2.6

Hardness: 6

Identified April 20, 2026More mineral →

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Physical properties

Formation & geological history

Formed through the deposition of silica from groundwater in cavities of igneous rocks or sedimentary layers. Primarily formed during volcanic activity or through low-temperature hydrothermal processes.

Uses & applications

Used widely in jewelry (beads, cabochons), ornamental stone carvings, and as a semi-precious collector's specimen. Historically used for making tools and seals.

Geological facts

This specimen shows the typical waxy 'orange-peel' texture and translucency of chalcedony. The name 'chalcedony' comes from the ancient Greek town of Chalkedon.

Field identification & locations

Identify in the field by its waxy luster, lack of visible crystals, and conchoidal (shell-like) fracture pattern. Commonly found in riverbeds, desert pavements, and volcanic regions.

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Mineral/Rock

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