mineral

Carnelian Agate

Silicon Dioxide (SiO2)

Hardness: 6.5-7 on Mohs scale; Color: Reddish-orange to brownish-orange; Luster: Vitreous to waxy; Crystal structure: Trigonal (cryptocrystalline); Cleavage: None; Specific Gravity: 2.58-2.64

Hardness: 6
Color: Reddish-orange to brownish-orange
Luster: Vitreous to waxy

Identified June 10, 2026More mineral →

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Physical properties

Hardness: 6.5-7 on Mohs scale; Color: Reddish-orange to brownish-orange; Luster: Vitreous to waxy; Crystal structure: Trigonal (cryptocrystalline); Cleavage: None; Specific Gravity: 2.58-2.64

Formation & geological history

Formed from the deposition of silica from groundwater into cavities in igneous rocks. The orange color is due to iron oxide impurities. Found in volcanic environments and alluvial deposits.

Uses & applications

Used primarily in jewelry (cabochons, beads), decorative carvings, and as a healing stone in lapidary arts. Historically used for making signet rings and seals.

Geological facts

Ancient Egyptians called carnelian 'the setting sun' and buried it with their dead to assist in the afterlife journeys. It was also used extensively in the Roman Empire for seal stones.

Field identification & locations

Identify by its translucency and characteristic orange-red hue. It often lacks the distinct banding of other agates but has a uniform, saturated color. Commonly found in riverbeds or beaches in regions such as India, Brazil, and Uruguay.