mineral

Carnelian and Dyed Agate

Chalcedony (Silicon Dioxide, SiO2)

Hardness: 6.5-7 on Mohs scale; Color: Reddish-orange (carnelian) and deep blue (dyed agate); Luster: Vitreous to waxy; Crystal Structure: Trigonal (microcrystalline); Cleavage: None; Specific Gravity: 2.58-2.64

Hardness: 6
Color: Reddish-orange (carnelian) and deep blue (dyed agate)
Luster: Vitreous to waxy

Identified June 26, 2026More mineral →

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Physical properties

Formation & geological history

Formed from silica-rich groundwater depositing in cavities of volcanic and sedimentary rocks. Carnelian gets its color from iron oxide impurities. The blue specimen appears to be artificially dyed, a common practice for ornamental stones.

Uses & applications

Used primarily in lapidary arts, jewelry making (cabochons and beads), and as pocket stones or collecting specimens for metaphysical interests.

Geological facts

Carnelian has been used for over 4,500 years, notably by ancient Romans for seal rings because hot wax does not stick to it. Agate is the birthstone for Gemini.

Field identification & locations

Identify by its waxy luster, lack of visible crystals (cryptocrystalline), and conchoidal fracture. Often found as rounded pebbles in stream beds or within volcanic host rocks. Dyed stones can sometimes be identified by concentrated pigment in minute cracks.

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Arenite (SiO2 based)

sedimentary

Schist

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Nephrite Jade

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Mineral/Rock

Banded Gneiss (River Rock/Pebble)

Gneiss (specifically a banded variety often found as a river rock)

Metamorphic Rock

Green Apatite on Albite

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mineral