Idar-Oberstein Points the Way

By Gary Roskin, G.G., FGA, Senior Editor -- JCK Online, 1/1/2002 2:00:00 AM

The Intergem show, held annually in Idar-Oberstein, Germany, is usually a reliable indicator of what will be available at the Tucson gem shows in February. Intergem 2001 hosted 110 exhibitors and more than 2,500 trade visitors from 38 countries. Here's what was hot:

There were considerable quantities and top qualities of Nigerian "Paraíba look-alike" tourmalines, the most talked-about gem at the show. According to reports, tourmalines from this new deposit—like those from Paraíba, Brazil—contain traces of copper which, when heated, create the neon electric colors for which Paraíbas are famous.

Some called the new African tourmaline "Indigo," reportedly for the mine that produces it, says Constantin Wild of Constantin Wild & Co., Idar. "The color is somewhat similar to original Paraíba, but more pastel blue [aquamarine color]," he notes. Most suppliers had some, and Wild sold a few. However, according to Werner Fürstenberg-Franzmann, general manager for gem cutters Herbert Fürstenberg, everyone was talking about it, but sales were questionable because prices seemed "a bit high." Tom Munsteiner, noted gem artist and son of the famous gem carver Berndt Munsteiner, says the natural amethyst-colored tourmalines from this new deposit are the ones heat-treated to create the Paraíba green/blue colors, but he notes that the process is not successful 100% of the time. He says that the unaffected amethystine tourmaline should be in Tucson along with the neon pastels.

Expect to see "berry" and "autumn" gem colors in 2002. Wild says they were the most popular in Idar. The hottest colors were reds, purples, and greens, as in tanzanite, tourmaline (rubellite, green, and the real Paraíba), garnet (tsavorite and demantoids), peridot, quartz (amethyst, citrine, and strawberry), Mexican opal, and sunstone.
Pastel colors are still in fashion, says Franzmann, noting that "chalcedony, aquamarine, turquoise, light amethyst, and light-colored tourmaline" were popular. Imperial topaz, pink topaz, and Santa Maria aquamarine also were heavily shopped. "The pastels were presented in a wide range of beryls and tourmalines," says Dieter Lorenz, Lorenz Designs. "Amethyst, a gem not popular for ages here in Europe, is back again!"

Even Lorenz was surprised to note that top-quality tanzanites are "still hot, even when prices are high." Munsteiner reports that "mandarin" orange spessartine garnets sold well.

Many loose-stone suppliers displayed jewelry, including necklaces, bracelets, and rings. Lorenz added a number of new models to his line of big carved ring stones. "Big rings are in," he says. "Especially in trendy colors, such as rose quartz, pink tourmaline, blue chalcedony, fire opal, etc." Lorenz expects to see a trend toward softer, more organic forms, away from the Bauhaus-inspired clear but somewhat "cold" designs.

Indigo Tourmaline from Nigeria

According to Constantin Wild of Idar-Oberstein, the Edoukou mine in Oyo, Nigeria (close to the border of Benin), has been producing for only a short while a variety of gem-quality tourmaline that owes its special color to the trace elements of copper and/or manganese. "This special color was only known previously as the legendary Paraíba tourmaline, mined in the state of Paraíba in northeastern Brazil," he says.

The natural color of this Nigerian tourmaline varies from blue-violet to amethystine color, which is predominantly caused by trivalent manganese, reports Wild. "To reduce the manganese absorption, the gems are heat treated, which allows the divalent copper to produce a blue color, comparable to aquamarine. The characteristically turquoise color—"neon blue"—of the Paraíba tourmaline has so far not been observed in the gems offered from this new mine."

Wild also notes that continuous heat treatment further reduces the manganese absorption, resulting in a mint-green color. "In the past, it was only necessary to detect copper in the spectroscope to confirm that a tourmaline was from Paraíba. But now, the same results can be seen in those stones from Nigeria," says Wild.

Constantin suggests that the two areas, Paraíba and Oyo, are geologically similar because the two land masses were connected millions of years ago. Based upon the continental drift theory—that is, all of the continents were originally part of the Gondwanaland super-continent—Nigeria and Brazil would have been right next to each other.

Wild also suggests that there should be plenty of stones available in the future. The partly rounded material suggests that the stones come from a secondary deposit. "We named this new material 'indigo tourmaline.' It stands for the blue tourmaline 'indicolite' as well as the name of the mine 'Edoukou.'"

For more information about the new Nigerian tourmaline, contact Wild at W. Constantin Wild & Co., Hauptstrasse 103, D-55743 Idar-Oberstein, Germany, log onto www.gemstone.de, or visit the company in Tucson at the GLDA show, Feb. 6-11, 2002, in the Upper Starlight Ballroom, Booths B1 and B2.