March/April 2003 • Giving Orange a Bad Name • Tucson Sales Surprisingly Solid • Chalcedony: A Gem for the Ages • News & Updates • In This Issue

Direct from Tucson
Here are some more interesting things our editors found in Tucson this year.
By Morgan Beard and Cara Woudenberg

People's Choice Awards | Tibits from Tucson | Beryllium Disclosure in Tucson | Back to Tucson Review

People's Choice Awards at the Manning House

The Gem Galleria gem art show, held at the Manning House on February 6-10, held its second annual People's Choice Awards, sponsored by Lightning Ridge Opal. The competition recognizes gem artists and their creations of gem art, carvings, and jewelry. Entries included pieces from the show's own exhibitors as well as outside entrants. There were two categories — gem art and jewelry, and show attendees voted on their favorites.

Helen Serras-Herman took first place in the jewelry art category for her Colombian emerald and opal necklace titled "Echoes."

Serras-Herman's Echoes necklace.

Michael Christie won in the gem art division for his piece "Ambrosia," a perfume bottle with jewelry components. His wife, gem artist Susan Allen, did the inernal carvings. This is Christie's second year to take first place in this category.

Michael Christie's Ambrosia.

Both winners were awarded a $500 cash prize and a piece of crystal opal, both donated by John Ternus of Lightning Ridge Opal.

Tucson Tidbits
A few things to mention that didn't make it into our main Tucson Review.

New Demantoid Garnet

Bill Larson of Pala International and Nicolai Kuznetsov examine a portion of the new demantoid garnet. Photo by Jeff Scovil.

Demantoid lovers were fortunate at this year's Tucson shows, where Pala International and a few Russian dealers brought even greater supplies of this long-missed gem.

Pala reports that about 20 kilos of the material were uncovered in a new vein at the old Kladovka mine this summer, more than anyone has seen since the deposit was originally discovered. Everyone will have to wait and see if that level of production will continue when the mines open again this summer.

For those who have trouble swallowing the high price tag on the Russian demantoid, help is on the way. Australian gem wholesaler Black Pearls & Gems Pty. is developing a demantoid garnet mine in South America that promises a much greater supply of the gem. The exact location of the mine is a closely-guarded secret, but according to the company, there's quite a lot of material coming out.

While the color isn't as bright green as the Russian material — it's more comparable to the color range of Namibian demantoid — the new demantoid has a healthy dispersion, the result of some unusual inclusions. Black Pearls & Gems is in the process of getting those inclusions analyzed, but this new find may turn out to be unique in the demantoid family.

Most of the material comes in sizes up to one carat, although they've found larger stones. Prices range from $180 per carat up to $6,000 per carat, and Black Pearls & Gems expect to be able to supply the market in quantity for the foreseeable future.

Afghani Emerald

In Tucson, Colgem E.L. 97 brought its new supply of emerald from Afghanistan, which is colored by chromium. "It's the only emerald in the world formed similar to Colombian emerald," said Colgem's Israel Eliezri. "The age is about the same also. It's the youngest emerald in the world. All of the other [mines] are contact metamorphic zones, and are very, very old. The Colombian and Afghani [were] mainly caused by hydrothermal supply."

The rough comes out like needles, but is very nicely formed with hardly any flaws. That means no need for oiling. Unfortunately, the material is also very small. There is a lot coming in carat sizes, but the bulk of it is melee.

There's also not a huge supply, so it won't be a major source. "It will not change the face of the emerald market," said Eliezri.

Eliezri says that due to the controversy with beryllium treatment of corundum, emerald treatments have been getting less attention and that emerald sales in general are up. "Emerald is going much better this year. Nobody cares what happens to emeralds anymore. . . . We sold much more than last year. Of course, the Afghani [material] helped."

Rainbow calsilica, cut through (left) and with the color layers (right).

Rainbow Calsilica from Mexico

Rainbow calsilica was a show-stopper at this year's shows, no doubt about it. With its bright striped layers of red-orange, blue, green, and yellow, it stands out in almost any crowd of gemstones. It's hard to believe that a material like this could be produced in nature — and, sadly, it isn't.

Rainbow calsilica has been sold as microcrystalline calcite in allophane from a mine in Chihuahua, Mexico. While the base material does indeed contain calcite, when scientists from the Swiss Gemmological Institute (SSEF) and Ghent University in Belgium examined a sample they found artists' pigments in the blue, yellow, and green layers, hematite in the red layers, and celestine in the black. "Our samples appear to have been made of pulverized carbonate rock that was mixed with pigments and stabilized with a polymer," concluded their report, which was published in the Winter 2002 issue of Gems & Gemology.

Indian Alexandrite

"It's proof that alexandrite is not an ugly color," boasts Manoj Kala of Tanzanite Inc., talking about a new find from India. Prized by many for its color change, the problem with alexandrite is that in many types of light it gets caught between its green and red extremes, looking more muddy than anything else.

But the alexandrite from this new deposit is a nice blue-green in most types of light. While the color-change isn't as impressive as alexandrite from other places — most of the material changes to a very light violet under incandescent light — it's got a unique selling proposition.

Quantities are sporadic, though. "It's a difficult stone for us to find," says Kala. "We're getting it little by little, but it took us four to five months to collect [a showcase full]. We're having problems filling orders for customers." In addition to limited quantity, it's found mostly in sizes under a carat, so you won't see it set in mass quantities.

Natural Pearls

With the advent of cultured pearls, to a certain extent the jewelry world forgot what a rarity natural pearlsare. Although they're certainly appreciated among connoisseurs, for the average person they remain out of reach, and to a certain extent out of awareness.

At the Tucson shows, Pacific Coast Pearls brought a new find of natural pearls from the Pteria Sterna oyster, in this case found off the coast of California. The color range on the pearls goes from white and gold to black with green and blue tints. Typical of natural pearls, most of the production is in baroque shapes, but there was at least one 11-mm round in the 2,500 carats they've bought over the past year. That size was unusual; about a third of the production by weight was seed pearls, with the rest in the middle range, and the largest at 234 carats. Prices range from $10 per carat to $1,000 per carat, depending on the size and quality.

Will there be more? Possibly, but not like the production that the company bought last year. "We got real lucky," says company owner Wes Rankin. "I think I nailed them all."