mineral (organic gemstone)

Precious Red Coral

Corallium rubrum / Corallium japonicum

AI-generated identification · may be incorrect

Hardness: 3-4 (Mohs), Color: Deep red to pink, Luster: Dull (natural) to Vitreous (polished), Crystal Structure: Trigonal (microcrystalline calcite), Specific Gravity: 2.6-2.7

Identified May 9, 2026More mineral (organic gemstone) →

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Physical properties

Hardness: 3-4 (Mohs), Color: Deep red to pink, Luster: Dull (natural) to Vitreous (polished), Crystal Structure: Trigonal (microcrystalline calcite), Specific Gravity: 2.6-2.7

Formation & geological history

Biological formation by marine polyps in deep-sea habitats, typically in the Mediterranean Sea or Pacific Ocean, secreting calcium carbonate skeletons over many years.

Uses & applications

Primarily used as a gemstone in high-end jewelry and religious ornamentation.

Geological facts

Precious coral is organic, like pearls or amber. It has been used as a protective amulet since Ancient Roman times and is known for its beautiful branching colonies.

Field identification & locations

Identified by its distinctive red color, branch-like structure, and potential wood-grain-like growth rings when viewed under magnification. Found in rocky seabeds at depths of 10 to 300 meters.

Other mineral (organic gemstone) specimens

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Precious Red Coral

Corallium rubrum (Calcium Carbonate, CaCO3)

Mineral (Organic Gemstone)

Coral (Precious Coral)

Corallium rubrum (Red Coral), Paracorallium japonicum (Momo Coral), Pleurocorallium elatius (Sardinian Coral), various other species within the Corallidae family. Chemically, it's primarily Calcium Carbonate (CaCO 3 ).

Mineral, Organic Gemstone