| August 2003
Gemstones & Pearls/News
The Sea's Vanishing Gift
Natural pink and red coral sizzles as a
fashion item, but the gem is becoming
more rare
Go ahead and label reddish gem coral indispensable. Why not? It performs in full glory as magnificent carvings, beads and couture jewelry, while also adorning inexpensive baubles at department stores. But as demand grows among consumers of all ages, so does the need to understand corals finite resources.
Coral is organic, made up of millions of exoskeletons of tiny marine animal polyps built up in tree-like colonies. Gem coral grows remarkably slowly in warmer ocean waters, most often between the Tropic of Cancer and the Tropic of Capricorn. Famous localities include Mediterranean sites, the Sea of Japan and Australias Great Barrier Reef. Italy is the present-day coral cultural, design and production center.
Large quantities of coral are bleached, dyed or stabilized with epoxy resin (or a combination) for use in jewelry. But because of the growing concern over the decimation of coral reefs, this gems days might be numbered.
Ocean Beauty
Calcareous (calcium-based) corals attraction is the assortment of red, russet, salmon and delicate pinkish-white shades the so-called precious corals. Others, such as rare blue varieties, are seldom seen in jewelry, except for black and golden coral made of the organic protein conchiolin and sold to tourists in the Caribbean and Hawaii. But when it comes to precious coral, the genus corallium rubrum (pink to red) rules the roost for several reasons:
- Versatility yields beads, pendants, pins, rings and earrings, carved or cabochon.
- The warm hues are easily matched with cool blues, such as turquoise.
- Diamond accents lift coral into the high-end.
- Its compatible with any precious metal.
History Class
In its Middle Ages heyday, Mediterranean coral was used in religious beads and small carvings and cameos. It was traded along ancient silk routes between Europe and Egypt and China as early as 100 B.C., says The History of Beads by Lois Sherr Dubin (Harry N. Abrams, 1987). Traders offered coral in exchange for silk, spices, porcelain and lacquer in the Far East and for many products from Africa.
Over time, enthusiasts came to believe coral would guard wearers from poison, enchantment or spells, along with ulcers, kidney stones and general misfortune. Once coral is broken, according to ancient belief, those protective powers ooze out.
Endangered Coral
Well over half of the coral reefs worldwide are at risk, and many of them are legally protected. Several genera and species have been added to the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES), though most listed now arent used in jewelry. Why the concern? Coral reefs are habitats for many species of fish and other wildlife. They also provide shoreline protection against erosion and act as ocean filters. Ongoing decimation has already had negative impacts on many marine environments and sealife.
The corallium precious corals are not on the CITES list for now, but they are in trouble because harvesting of this material is not being actively managed, says Dr. A. Bruckner, a coral reef ecologist with the National Oceanic and Atmospheric Administration who is working to get pink coral on the CITES list. You just dont see any of the big, old colonies of pink coral its getting thinner and thinner.
Jewelry coral expert Roben Hogobian of R.H. & Co., Glendale, CA, confirms coral is harder to find in shallower areas of the Mediterranean. Divers have to go a lot deeper than they did just six years ago, he says.
Treatments
More affordable forms of coral are widespread in the jewelry market, but they generally are subject to treatment such as:
- Bleaching, which achieves uniformity in coral with mottled coloration.
- Dyeing deep red oxblood or light pink angelskin. Some is bleached first.
- Impregnation with epoxy resin. The growth structures are easily visible.
- Reconstitution of poor-quality coral thats ground into a powder then mixed with a binding agent such as epoxy resin to form blocks that can be formed for use in jewelry. Such material should not be called coral. Corals fibrous, layered structure and tree-ring structures are not apparent in this material.
The Imitators
For customers who cant afford or dont want coral, there are substitutes. One is a Gilson imitation in red and pink. Its semitranslucent to opaque like coral, but it exhibits a granular structure rather than the wavy fibrous characteristic of natural coral. Dyed chalcedony and glass can be distinguished from coral because of the lack of structure, appearance and specific gravity.
RH & Co., Glendale, CA; (800) 242-1233.
Behnam Jewelry Corp., New York City; (212) 302-7800.
by Robert Weldon, G.G.
All photos by Robert Weldon.
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From left, oxblood red coral beads are 12.5-17mm and up, pink-orange button cabochons weigh a total of 125.84 carats, the red pear-shaped coral is 81.87 carats and the salmon-orange coral beads range from 17mm to 24mm. Gems are courtesy of R.H. & Co., Glendale, CA. |
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Silver bracelet, earrings and ring with color-enhanced red coral are from the Frederica Collection by Behnam Jewelry Corp., New York City. |
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This 2-in. long salmon-pink coral was carved in Italy. Gem courtesy of R.H. & Co., Glendale, CA. |
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The photo at left shows inexpensive, brittle branch coral before epoxy impregnation. The photo right shows coral after impregnation and ready to be fashioned into cabochons. Courtesy of Colbaugh Processing, Kingman, AZ.
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