mineral

Chalcedony (Agate/Carnelian variant)

Silicon Dioxide (SiO2)

Hardness: 6.5-7 (Mohs scale); Color: Translucent tan to honey-yellow; Luster: Waxy to vitreous; Crystal Structure: Cryptocrystalline (Trigonal/Monoclinic); Cleavage: None (Conchoidal fracture); Specific Gravity: 2.58–2.64

Hardness: 6
Color: Translucent tan to honey-yellow
Luster: Waxy to vitreous

Identified April 25, 2026More mineral →

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Physical properties

Formation & geological history

Formed from the deposition of silica-rich water in cavities of volcanic or sedimentary rocks. This specific piece appears water-worn, suggesting it was found in a riverbed or alluvial deposit.

Uses & applications

Commonly used for lapidary work, decorative carvings, jewelry beads, and as a popular focus for rockhounding collectors.

Geological facts

Chalcedony is a broad term for all cryptocrystalline quartz. When it exhibits banding, it is called Agate; when it is reddish-brown, it is Carnelian. This translucent honey-colored variety is often found in river gravels globally.

Field identification & locations

Identify in the field by its waxy texture, inability to be scratched by a steel knife, and smooth, curved (conchoidal) fracture surfaces. Commonly found in riverbeds, beaches, and desert washes.

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Mineral/Rock

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