mineral

Carnelian

Carnelian (Cryptocrystalline Quartz, SiO2)

AI-generated identification · may be incorrect

Hardness: 6.5-7 on Mohs scale; Color: Orange, reddish-brown, brownish-red; Luster: Vitreous to waxy; Crystal Structure: Trigonal (microcrystalline); Cleavage: None; Specific Gravity: 2.58-2.64

Hardness: 6
Color: Orange, reddish-brown, brownish-red
Luster: Vitreous to waxy

Identified June 28, 2026More mineral →

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Physical properties

Hardness: 6.5-7 on Mohs scale; Color: Orange, reddish-brown, brownish-red; Luster: Vitreous to waxy; Crystal Structure: Trigonal (microcrystalline); Cleavage: None; Specific Gravity: 2.58-2.64

Formation & geological history

Formed in volcanic and sedimentary rocks as groundwater rich in silica deposits minerals in cavities and veins. The reddish hue is caused by iron oxide (hematite) impurities. It can be found in ancient geological layers across various ages.

Uses & applications

Extensively used in jewelry (cabochons, beads, rings), decorative ornaments, stone carvings, and as a popular collectible for enthusiasts of tumble-polished stones.

Geological facts

In ancient times, carnelian was believed to protect the wearer from bad luck and was used by Egyptian pharaohs in seals and amulets. It is one of the oldest gemstones used by humans, dating back to at least the Neolithic period.

Field identification & locations

Identify by its translucent to semi-opaque orange body color and waxy luster when polished. It lacks the banding typically seen in agate. To find it in the field, look in gravel beds or volcanic regions in India, Brazil, and Uruguay.