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Coral

The natural pearl isn’t the only worldwide casualty of pollution in the planet’s seas. Now coral, the other great organic sea-gem, is in big trouble too -- at least in its finest, most coveted red colors.

Highly treasured in ancient India, Persia and Rome, coral is nearly as much a mainstay of gemstone artisanry as amber and ivory, especially with Native American craftsmen. As with other organic gems, coral was widely believed to have medicinal and mystical powers. Even today, coral powder is a popular aphrodisiac in India, which use prompts some gatherers to dynamite coral reefs. Such tactics, of course, only aggravate the fine-goods supply problem. But coral must fend off graver threats than TNT.

As a living organism, coral faces a slew of challenges to its survival, especially as the waters in which it lives become progressively contaminated. The creation process of the gem coral is peculiar and complicated. But, simply put, here’s how it works: A multi-cellular animal called the coral polyp bands together in colonies with millions of its fellow polyps. For protection, each secretes a protective jacket for itself of pure calcium carbonate into which it retreats when threatened or not feeding. As the colony builds these shells, they couple together into branches and, if large enough, reefs.

Unfortunately, these calcium carbonate structures -- which Gemological Institute of America chief gemologist John Koivula calls “condominium complexes”-- cannot withstand merciless predators such as the Crown of Thorns starfish which attach themselves to the colony and suck out all the lives. Often the polyps will abandon their homes when water conditions change for the worse. Whether ravaged or deserted, it is these coral skeletons (Koivula calls them “abandoned housing projects”) that coral fishers process into beads, cabs and carvings.

Because coral is pure calcium carbonate, it is sensitive to chemicals, detergents, perfumes, even body acids which can eat away at it. That’s why dealers and gemologists recommend periodic cleaning of coral in a mild soapy solution to rid it of all these abrasives. Even so, some softer corals, such as those from the Mediterranean, may need re-polishing every few years or so.

Red Sales In The Sunset

Luckily, some corals are more resistant to chemicals and acids. The toughest, according to a Los Angeles coral specialist, come from the Sea of Japan, which is also the prime source of true ox-blood coral. “The Mediterranean produces red coral, too,” he adds, “but it is not as hard as the material from Japanese waters.”

In recent years, Taiwanese coral fishers have replaced the Italians, famous for centuries as coral carvers and cutters, as the main harvesters of this gem off Japan. But lately the Japanese fish and wildlife authorities have been enforcing strict coral quotas in the Sea of Japan and, as a result, sharply curtailing fishing activity in these waters.

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Coral