mineral

Carnelian (Chalcedony)

Silicon Dioxide (SiO2)

Hardness: 6.5-7 on Mohs scale; Color: translucent orange to reddish-orange; Luster: vitreous to waxy; Crystal structure: trigonal (microcrystalline); Cleavage: none; Specific gravity: 2.58–2.64.

Hardness: 6
Color: translucent orange to reddish-orange
Luster: vitreous to waxy

Identified July 24, 2026More mineral →

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Physical properties

Hardness: 6.5-7 on Mohs scale; Color: translucent orange to reddish-orange; Luster: vitreous to waxy; Crystal structure: trigonal (microcrystalline); Cleavage: none; Specific gravity: 2.58–2.64.

Formation & geological history

Formed through precipitation of silica-rich solutions in cavities and veins of volcanic rocks, as well as in sedimentary environments.

Uses & applications

Used primarily in lapidary work, jewelry making, carved beads, decorative objects, and as a popular tumbled gemstone for rock collectors.

Geological facts

Carnelian has been used in jewelry for over 4,000 years. Ancient Egyptians called it 'the setting sun' and buried it with pharaohs to protect them in the afterlife.

Field identification & locations

Identified by its warm orange hue, translucency when held to light, smooth fracture surface, and resistance to scratching by steel. Commonly found in river gravels, beaches, and weathered volcanic deposits.