mineral

Carnelian Agate

Chalcedony (SiO2) with iron oxide inclusions

Hardness: 6.5–7 (Mohs scale); Color: Orange to reddish-brown; Luster: Waxy to vitreous; Crystal Structure: Trigonal (Microcrystalline); Cleavage: None; Fracture: Conchoidal; Specific Gravity: 2.58–2.64.

Hardness: 6
Color: Orange to reddish-brown
Luster: Waxy to vitreous

Identified April 4, 2026More mineral →

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Physical properties

Formation & geological history

Formed through the deposition of silica from groundwater in the cavities of igneous rocks, particularly lavas. The reddish-orange tint comes from iron oxide (hematite) impurities. It can be found in sedimentary environments through erosion.

Uses & applications

Used primarily in jewelry (beads, cabochons, rings), ornamental carvings, and seal stones. Historically used for signet rings and amulets.

Geological facts

Carnelian was highly valued by Ancient Egyptians who called it 'the setting sun.' In the Islamic world, it is considered a sacred stone often engraved with religious texts. It is the birthstone for the zodiac sign of Virgo.

Field identification & locations

Identify in the field by its waxy luster, translucency, and warm orange hue. Often found as rounded pebbles in gravel beds or river washing near volcanic regions. Commonly found in Brazil, India, Uruguay, and Madagascar.

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