Precious coral

Precious coral, also called red coral, refers to a group of marine corals in the genus *Corallium*. What sets them apart is their hard, vividly colored skeleton—ranging from deep red to pinkish-orange—which has long been used to make jewelry.

These corals live on rocky seafloors where sediment is scarce, preferring dark spots like deep waters, shadowy caves, or crevices. The first species identified, *Corallium rubrum* (once known as *Gorgonia nobilis*), is mostly found in the Mediterranean Sea. It grows between 10 and 300 meters deep, though the shallower areas have been heavily fished out. In the underwater caves near Alghero, Sardinia—part of the "Coral Riviera"—it thrives at depths of just 4 to 35 meters. The same species also appears in the Atlantic near the Strait of Gibraltar, around the Cape Verde Islands, and off southern Portugal. Other *Corallium* species come from the western Pacific, especially near Japan and Taiwan, where they live 350 to 1,500 meters down in areas with strong currents.

Like other Octocorallia, red corals look like small, leafless bushes and can reach about a meter tall. Their valuable skeleton is made of tightly packed spicules of hard calcium carbonate, colored red by carotenoid pigments. In living corals, the skeletal branches are covered with a soft, bright red skin, from which many white, retractable polyps stick out. These polyps have eightfold radial symmetry.

The hard skeleton of red coral is naturally dull but can be polished to a glassy shine. Its colors range from pale pink to deep red—so much so that "coral" is also the name for such hues. Because of its lasting color and gloss, people have harvested precious coral for decoration since ancient times. Coral jewelry has turned up in Egyptian and prehistoric European burials and is still made today. It was especially fashionable in the Victorian era. On the Mohs scale, precious coral has a hardness of 3.5. Because it’s soft and opaque, it’s usually cut as a cabochon or made into beads.

Around the start of the first millennium, coral was heavily traded between the Mediterranean and India, where it was prized as a sacred, mysterious substance. Pliny the Elder noted that before India’s huge demand, the Gauls used coral to decorate their weapons and helmets. But by his time, so much was going east that it was rarely seen even where it was produced. Among the Romans, coral branches were hung around children’s necks to ward off danger, and the material was thought to have many medicinal powers. This belief in coral as a charm lasted through the Middle Ages, and into early 20th-century Italy—where it’s called *cerasuolo*—it was worn to protect against the evil eye and by women hoping to cure infertility.

From the Middle Ages on, European Mediterranean communities fiercely competed for rights to coral fisheries off the African coast. The story of Torre del Greco is deeply tied to coral, with records going back to the 1400s. In 1790, the Royal Society of Coral was set up there to process and sell coral fish, showing that fishing had flourished in the town for years. On December 22, 1789, Ferdinand IV of Bourbon enacted the Coral Code (drafted by Neapolitan jurist Michael Florio) to regulate coral fishing, which at the time involved sailors from Torre del Greco, locals, and people from Trapani. This regulation didn’t work as hoped. Starting in 1805, when Paul Bartholomew Martin (of French Genoese origin) founded the first coral manufacturing factory in Torre del Greco, the town’s golden age for coral processing began, as fishing came increasingly under the control of its fishermen. From 1875, Torre del Greco started working with Sciacca coral, and a coral manufacturing school opened there in 1878 (closing in 1885, reopening in 1887), leading to a coral museum in 1933. Later, Japanese coral was processed, sourced from markets in Chennai and Kolkata. For a short time, Tunisian fisheries were secured by Charles V for Spain, but the monopoly soon went to the French, who held it until the Revolutionary government opened trade in 1793. The British briefly controlled the fisheries around 1806, but they later returned to French hands. Before the French Revolution, much coral trade centered on Marseille, but it then shifted largely to Italy, with raw material and processing concentrated in Naples, Rome, and Genoa.

In Greek mythology, coral’s origin comes from the story of Perseus. After petrifying the sea monster Cetus, who was threatening Andromeda, Perseus set Medusa’s head on the riverbank while he washed his hands. When he picked it up, her blood had turned the seaweed (or reeds, in some versions) into red coral. That’s why the Greek word for coral is *Gorgeia*, since Medusa was one of the three Gorgons. Poseidon lived in a palace made of coral and gems, and Hephaestus first crafted his work from coral. The Romans believed coral could protect children from harm.