Precious Red Coral

Physical Properties

Hardness: 3.5 - 4 on Mohs scale; Color: bright red to orange-red; Luster: vitreous to waxy when polished; Crystal structure: Trigonal (amorphous microcrystalline); Specific gravity: 2.6 - 2.7.

Formation & Geological History

Formed by tiny marine polyps in subtropical and tropical waters (caves and crevices). The skeletal remains of the polyps accumulate and harden over centuries into a branching structure.

Uses & Applications

Primarily used in jewelry (beads, cabochons, carvings) and by collectors. Historically used in talismans and alternative medicine.

Geological Facts

Red coral is an organic gemstone, meaning it is biological in origin. It has been used for jewelry since ancient Egyptian and Roman times, often believed to protect the wearer from evil.

Field Identification & Locations

Identify by looking for a fine, wood-grain-like texture under a loupe. It often contains small pits or cavities. Avoid pieces that feel like plastic or show dye concentrated in cracks.

Identified on: 4/20/2026

Mode: Standard