mineral

Carnelian (Chalcedony)

Silicon Dioxide (SiO2)

Hardness: 6.5-7 Mohs; Color: Orange, reddish-brown, brownish-red; Luster: Waxy to vitreous; Crystal Structure: Trigonal (cryptocrystalline); Cleavage: None; Specific Gravity: 2.58-2.64

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

Identified May 19, 2026More mineral →

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Physical properties

Hardness: 6.5-7 Mohs; Color: Orange, reddish-brown, brownish-red; Luster: Waxy to vitreous; Crystal Structure: Trigonal (cryptocrystalline); Cleavage: None; Specific Gravity: 2.58-2.64

Formation & geological history

Formed through the deposition of silica in cavities of volcanic rocks or sedimentary environments. The red color is caused by impurities of iron oxide (hematite). Occurs in ancient volcanic flow regions.

Uses & applications

Widely used in jewelry (cabochons, beads), decorative carvings, and as a healing stone in metaphysical practices. Historically used for signet rings and wax seals.

Geological facts

In ancient Egypt, Carnelian was considered a symbol of life and was often buried with the dead to help them in their journey to the afterworld. It is one of the oldest known gemstones used by humans.

Field identification & locations

Identify by its translucent orange hue and waxy surface. Look for it in riverbeds or coastal gravels in volcanic regions like Brazil, India, Uruguay, or Madagascar.