mineral

Carnelian

Chalcedony (Silicon Dioxide, SiO2)

Hardness: 6.5-7 (Mohs). Color: Orange, red, brownish-red. Luster: Waxy to vitreous. Crystal structure: Trigonal/Microcrystalline. Cleavage: None. Specific gravity: 2.58-2.64.

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

Identified May 15, 2026More mineral →

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Physical properties

Hardness: 6.5-7 (Mohs). Color: Orange, red, brownish-red. Luster: Waxy to vitreous. Crystal structure: Trigonal/Microcrystalline. Cleavage: None. Specific gravity: 2.58-2.64.

Formation & geological history

Forms in volcanic environments through the infiltration of silica-rich water into cavities or gas bubbles (amygdules) within lava rocks. Its red color comes from iron oxide (hematite) impurities.

Uses & applications

Primarily used in jewelry for cabochons, beads, and carvings. Also popular as a tumbled stone for collectors and metaphysical practices.

Geological facts

In ancient times, carnelian was believed to protect the wearer from bad luck and anger. It was frequently used in Roman signet rings for stamping wax seals because the wax doesn't stick to it.

Field identification & locations

Identify by its waxy luster and translucent orange-red hue when held to light. Common locations include Brazil, India, Uruguay, Madagascar, and parts of the United States (Washington and Oregon).