mineral

Carnelian

Chalcedony (SiO2) with iron oxide impurities

AI-generated identification · may be incorrect

Hardness: 6.5-7 (Mohs scale); Color: Brownish-red to orange; Luster: Waxy to vitreous; Crystal structure: Trigonal/Microcrystalline; Cleavage: None; Specific Gravity: 2.58-2.64

Hardness: 6
Color: Brownish-red to orange
Luster: Waxy to vitreous

Identified July 19, 2026More mineral →

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Physical properties

Hardness: 6.5-7 (Mohs scale); Color: Brownish-red to orange; Luster: Waxy to vitreous; Crystal structure: Trigonal/Microcrystalline; Cleavage: None; Specific Gravity: 2.58-2.64

Formation & geological history

Formed in low-temperature hydrothermal environments where silica-rich fluids deposit in cavities of volcanic rocks. The orange-red color comes from hematite or iron oxide inclusions.

Uses & applications

Commonly used in jewelry, as cabochons, for beads, and in lapidary art such as intaglio carving and seal-making.

Geological facts

Carnelian is one of the oldest gemstones in history; it was used by the Ancient Egyptians for amulets and by Romans for signet rings because hot wax doesn't stick to its smooth surface.

Field identification & locations

Identify by its characteristic warm orange-red translucency and waxy luster. In the field, look for smooth, rounded pebbles in riverbeds or volcanic areas. Small, rough garnets or jaspers can look similar, but carnelian is notably more translucent.