mineral

Carnelian

Carnelian (SiO2 with iron oxide impurities)

Hardness: 6.5–7 (Mohs scale); Color: Orangey-red to brownish-red; Luster: Waxy to vitreous; Crystal structure: Trigonal (cryptocrystalline); Cleavage: None; Relief: Low

Hardness: 6
Color: Orangey-red to brownish-red
Luster: Waxy to vitreous

Identified June 8, 2026More mineral →

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Physical properties

Hardness: 6.5–7 (Mohs scale); Color: Orangey-red to brownish-red; Luster: Waxy to vitreous; Crystal structure: Trigonal (cryptocrystalline); Cleavage: None; Relief: Low

Formation & geological history

Formed in cavities and veins of volcanic and sedimentary rocks. The color is caused by iron oxide impurities like hematite. Found in igneous environments where silica-rich fluids deposit in gas bubbles (vesicles).

Uses & applications

Commonly used in jewelry, lapidary art, beads, cabochons, and as a semi-precious healing stone in metaphysical communities.

Geological facts

In ancient Rome, carnelian was used for signet rings to seal letters because hot wax does not stick to it. It has been used in jewelry for over 4,500 years.

Field identification & locations

Identify by its translucent reddish-orange color, waxy luster, and conchoidal fracture. Often found along riverbeds or in coastal gravels near volcanic sites.

Other mineral specimens

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Sandstone (with potential mineral staining/concretions)

Arenite (SiO2 based)

sedimentary

Schist

Metamorphic

Epidote

Epidote | Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH)

metamorphic

Nephrite Jade

Nephrite

Mineral/Rock

Banded Gneiss (River Rock/Pebble)

Gneiss (specifically a banded variety often found as a river rock)

Metamorphic Rock

Biotite Schist

Biotite-rich Schist [K(Mg,Fe)3AlSi3O10(F,OH)2]

metamorphic