gemstone

Carnelian

SiO2 (Silicon Dioxide with Iron Oxide impurities)

AI-generated identification · may be incorrect

Hardness: 6.5-7 (Mohs scale), Color: Orange to reddish-brown, Luster: Vitreous to waxy, Crystal Structure: Trigonal (microcrystalline/cryptocrystalline), Translucency: Translucent to opaque

Hardness: 6

Identified July 5, 2026More gemstone →

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Physical properties

Hardness: 6.5-7 (Mohs scale), Color: Orange to reddish-brown, Luster: Vitreous to waxy, Crystal Structure: Trigonal (microcrystalline/cryptocrystalline), Translucency: Translucent to opaque

Formation & geological history

Formed as a microcrystalline variety of quartz through silica-rich water deposition in volcanic rocks or sedimentary environments. Iron oxide impurities provide the red-orange tint. Found in geodes and as nodules.

Uses & applications

Primarily used as a gemstone for jewelry, Intaglio carvings, beads, and metaphysical specimens.

Geological facts

Ancient civilizations such as the Romans and Egyptians used carnelian for signet rings and amulets because it doesn't stick to hot wax. It was highly valued in antiquity as a gem for kings.

Field identification & locations

Identifiable by its warm orange hue and waxy luster. Frequently found in riverbeds or coastal areas in India, Brazil, and Uruguay. Look for a conchoidal (shell-like) fracture pattern when broken.