Mediterranean — The Sea That Has Supplied Coral to the Trade Since Antiquity
Mediterranean — The Sea That Has Supplied Coral to the Trade Since Antiquity
Corallium rubrum from the Italian, Spanish, and North African coasts, the historical benchmark for red coral
The Mediterranean Sea has been the principal historical source of fine red coral — Corallium rubrum, sometimes called precious coral or Italian coral — for jewellery and ornamental carving since antiquity. The Mediterranean material set the global standard for the colour and texture of fine coral, and the harvesting traditions of the Italian, Spanish, and North African coasts shaped the international coral trade for more than two thousand years. Modern environmental regulation, depletion of accessible beds, and competition from Pacific corals have changed the trade landscape, but Mediterranean material remains the reference against which other coral sources are measured.
The species and its biology
Corallium rubrum is a slow-growing colonial cnidarian that secretes a calcium carbonate skeleton in branching, tree-like forms. The skeleton — the part used in jewellery — is composed of crystalline calcite with a dense, fine-grained texture that takes a high polish. The colour ranges from pale pink (often called angel skin in trade) through orange-red and salmon to deep red (the so-called oxblood), with the deepest, most uniformly saturated material commanding the highest prices.
The species lives at depths of approximately 30 to 200 metres, attached to underwater cliffs and overhangs. Growth rates are extremely slow — a few millimetres per year for the trunk diameter — meaning that a substantial coral branch may represent decades of growth. This slow growth is the principal sustainability challenge for the species: harvesting can outpace regrowth on a scale that puts the resource at long-term risk.
Historical and modern harvesting areas
The traditional Mediterranean coral grounds run along the coasts of Italy (Sicily, Sardinia, the Ligurian coast, and the Naples region historically), Spain (the Costa Brava and the Balearic Islands), France (the Côte d'Azur and Corsica), and the North African coast from Morocco through Algeria and Tunisia. Italian fishermen developed many of the traditional harvesting techniques, including dredges and the more recent practice of diving-based selective harvest. Naples and Torre del Greco near Naples remain the principal Italian coral-working centres, with carving and bead workshops in the area continuing the centuries-old tradition.
Harvesting is now regulated under Italian, Spanish, and EU rules, with quotas, minimum sizes, and seasonal limits intended to allow stocks to recover. CITES Appendix III listing in 2009 added an international trade-permitting layer for some Pacific coral species, with Mediterranean Corallium rubrum subject to its own regional management framework. Despite these measures, the supply of fine Mediterranean coral has tightened considerably in the past several decades.
Material characteristics and grading
Mediterranean coral is graded primarily by colour, density, and freedom from pits and worm-holes. The trade colour categories include the pale-pink angel skin, the salmon-orange moro, the medium red secondo coloro, and the deep oxblood red — each with regional Italian trade names that vary between Naples, Torre del Greco, and other working centres. Density and freedom from natural cavities matter for both polishing quality and durability in jewellery use.
Hardness is approximately 3.5 on the Mohs scale — soft compared with mineral gemstones — which constrains the wearable applications and demands careful setting. The traditional bezel, cup, and prong settings used in Italian coral jewellery reflect the need to protect the soft material from wear. Cleaning should be by mild soap and warm water; ultrasonic and steam cleaning are not recommended.
The modern trade picture
Fine Mediterranean coral has become substantially more scarce and valuable over the past several decades, with prices for top-quality oxblood and angel-skin material rising several-fold. Pacific corals — Corallium japonicum, Paracorallium japonicum, and other species from Taiwan, Japan, and Hawaii — supply the bulk of the modern jewellery market, with Mediterranean material representing the high-end and traditional segment. Antique Italian coral jewellery from the eighteenth and nineteenth centuries is itself a substantial collecting category, with carved cameos, bead necklaces, and figural pieces commanding premium prices on both the material and the craft.