Treasures from Tucson

Quantity was the operative word at Tucson: 33 separate shows, gems by the pile, bushel bags of pearls. Recent mine finds included Russian demantoid—in kilo bags—at Pala International’s booth at the AGTA show, and spectacular transparent rhodocrosite from the Sweet Home Mine in Colorado, shown at Iteco.

The standards—ruby, emerald, sapphire, tanzanite, etc.—were well represented along with the unusual and the bizarre. The unusual included demantoid from Iran that gem hunter Gary Bowersox carried around in his pocket. The bizarre included the inevitable coprolite (fossilized dinosaur dung) and a “new” supply of 1950s and 1960s “Ford-ite”—agate-like color-layered cabochons of old Ford Motor Co. paint!

On the education front, there were dozens of seminars, panels, association conferences, press conferences, and the usual meet-me-in-the-aisle conversations. All provided attendees with worthy distractions such as the latest scuttlebutt on beryllium-treated corundum, a method for evaluating the quality of jadeite, and tips on photographing gems.

How’s business? In general, sales were up and dealers were pleased. Buyers filled the aisles of the three major gem shows: the American Gem Trade Association (AGTA) GemFair in the convention center, the GJX Gem & Jewelry Exchange tent, and the Gem and Lapidary Dealers Association (GLDA) show at the Radisson.

AGTA executive director Doug Hucker reports that numbers at GemFair were up significantly from last year, with approximately 10,000 buyers in attendance over the six-day show. Some dealers mentioned that only half as many international wholesalers and retailers were in attendance compared with last year’s international contingent.

Beryllium sapphire. Corundum was the most talked-about stone at all the venues. There was a seemingly endless round of seminars, panels, and press conferences dedicated to discussing the beryllium-treated (bulk diffusion) material.

In an effort to maintain the integrity of the U.S. market, the final Corundum Conference—held after a week of closed-door meetings—concluded with the announcement of a disclosure policy for certain corundum and corundum jewelry products for sale in the United States. AGTA, Jewelers of America, the American Gem Society, and the Jewelers Vigilance Committee worked together to produce the following outline:

  • The international scientific and gemological communities have confirmed that the “new” treatment being used on certain corundum is a diffusion (bulk/lattice) treatment. The additives being used create new colors and alter existing colors.

  • According to Federal Trade Commission Guidelines and industry practices, this treatment must be disclosed at point of purchase by all sellers, to all buyers, at all levels of the trade.

  • Because of lack of consistency and/or uniformity in coloration of some stones, re-cutting and polishing could affect color, creating increased concern for the consumer in terms of care requirements.

  • Based on these concerns, buyers of corundum should consider establishing written vendor agreements stipulating a requirement for such disclosure and further requiring the right to return material subject to this treatment [if treatment is] not disclosed at the time of sale.

  • U.S. laboratories, which are engaged in research on this matter and cooperating with the international gemological community, are committed to continue efforts to identify this treatment, support the trade, and protect the consumer.
    Laboratories are still unable to identify this material 100% of the time. This makes even the experts uncomfortable with the purchase, sale, and appraisal of all colors of corundum.

At the shows, AGTA dealers—committed to full disclosure—weren’t shy with their signage, touting more “natural/unheated” material than in years past. Those that didn’t stock natural unheated sapphires were quick to mention that they had spot-checked their supply using GIA’s and AGTA’s laboratories to test for beryllium enhancement. Overall, fancy-color sapphires and rubies sold well if dealers could prove they were natural, unheated, or traditionally heated. Absent proof that beryllium diffusion treatment had not been done—as was the case in many other venues—corundum remained in the showcase.

Bob Kane at Fine Gems International made sure people noted that his Montana sapphires were enhanced only by the more traditional heat treatment and that the company guarantees the Montana origin of the gems. Natural unheated Montana Yogos also did well.

One company in the GJX show was selling parcels of small calibrated beryllium-treated sapphires for $10/ct., which was quite a fall from last year’s prices seen elsewhere—$60/ct. to $800/ct.

Pearls. Attendees saw a plethora of pearls of medium to low quality, in both Chinese freshwaters (CFWP) and Tahitians. There were plenty of Tahitian pearls for less than $50 apiece and mounted fine-quality pearls for under $100 each.

Lois Berger, pearl expert and appraiser with Fuller & Associates in McLean, Va., believes that despite talk of price stabilization, over-production by thousands of small independent farmers will spawn a glut of pearls by the end of this year. “Prices will be up for grabs,” she predicts. The only exception is the Japanese akoya market, which certainly isn’t suffering the effects of over-production.

At the other end of the spectrum, Berger noted the absence of high-end CFWPs. “You will not find a real round high-luster Chinese freshwater—not in abundance,” she says. Interestingly, however, she did find more blemished goods with great luster. “So what’s going on?” she wondered out loud, hinting at possible polymer coatings.

Rohm-ing for beads. Faceted beads were ubiquitous, and there was at least one standout exhibitor—Rohm, of Linz, Austria, exhibiting for the first time in Tucson in the GJX tent. The company had an impressive selection of medium to high-end gem bead necklaces and loose strands, in a large number of shapes, sizes, and types.

Rohm actually specializes in corals, and the company carries Sardegna, Deep Sea, Midway, Momo, Mushi, Aka, Moro, Angel Skin, Garnet, and Scotch varieties in beads, branches, cylinders, and barrel shapes.

Synthetic diamonds. Chatham Created Gems is back in the synthetic diamond game, and Florida’s Gemesis also had product for sale. Tom Chatham showed the latest in synthetic gem-quality diamond rough production in grown (not enhanced) pink, pink-orange, greenish-blue, blue, and yellow synthetic crystals. Expect to see cut stones soon.

Synthetic diamond manufacturer Gemesis Corp., Sarasota, Fla., is already in production, with a line of yellow, orangy-yellow, and yellowish-orange gem-quality synthetic faceted diamonds. Although this was the company’s first Tucson gem show, interest in the product was significant.

Diamond cut. GIA again administered visual comparison (observation) tests using diamonds under standardized conditions. GIA will use the results to evaluate how various aspects of brilliance, fire, and other factors can affect overall appearance.

Over the past year, GIA has conducted research on diamond appearance using these observation tests. It has conducted more than 40,000 observations of more than 1,000 different diamonds. No diamond evaluation methodology currently used in the trade has been empirically tested in this manner.

In my own experience as a gemologist, I’ve seen some “ideal” cuts that didn’t look quite as good as others, but this study also shows me that some proportions can be far from the traditional “ideal” but still look very good.

This is the second time I’ve participated in the diamond-cut study, and my choices were surprising. In the first group of four stones, I chose a stone with steep crown angles (36.4°) and a deep pavilion angle (41.5°) as my most preferred, even over one that appeared to be an “ideal” cut. In the second group, I chose a stone with very shallow crown angles (24.1°) and a steep pavilion (42.2°). I felt vindicated by group 3, since I didn’t like any of the four, all of which had relatively deep total depths. In the last group of four, I somehow chose what looks like an old Tolkowsky stone with a 52% table, 33.7° crown (almost 34°), and a 43.5% pavilion.

GIA’s cut research project has, on a large scale, drawn the same conclusions that I did at Tucson. GIA’s Al Gilbertson, a lead technical scientist for the project, notes that the organization believes “there are many ways to cut diamonds to achieve high results for brilliance and fire, and that some of those proportion sets may be surprising.”

Treasure lost: Remembering Gil Roberts. Earlier this year, the trade lost another gem artist when North American gem carver Gil Roberts died at the age of 51. Members of Gem Artists of North America (GANA) paid tribute to Roberts with images of his work as well as personal tributes.

Completely self-taught in the art of gem carving, Roberts refined his skills and talent with an unlikely medium—wood. Roberts’s early experience was in furniture design and wood sculpture, but he soon turned to gemstones, incorporating carved stones into his wood creations. He began designing wood jewelry, then switched to silver and goldsmithing, still setting stones carved by other artists. Eventually, his fascination with gems led him to carve his own. Gemstones became his focus, and carving became his passion.

A meeting with Canadian gem carver Thomas McPhee inspired Roberts to try figurative carving. In quartz, he found the perfect medium for his creative expression, and in the following decade produced an impressive body of small sculptures, jewelry, and internally carved scenes. Roberts had recently combined his goldsmithing skills with gem carving to create an elegant and breathtaking line of carved crystal perfume bottles set with gold and precious gems.

He once said, “In my dance through life, I find the term ‘creativity’ most powerful and meaningful.…The basic element of creation is the spark from which thought and dream manifest into reality.”

Roberts often spent months, even years, studying a rough crystal before finally revealing the image within. But once involved in the process, he relentlessly carved and polished to achieve the degree of perfection characteristic of his work. In the midst of several projects at once, Roberts often moved back and forth between pieces, averaging 200 hours per piece.

Inspired by the stunning Blue Ridge Mountains surrounding his home in rural southwest Virginia, Roberts successfully captured in his pieces the grace and power of the predatory birds native to the region. Other influences included Gothic cathedrals, Art Nouveau, and scenes from his travels, including areas of the southwestern United States.

The delicate grace and beauty that characterize the creations of Gil Roberts—from the fluid lines of a perfume bottle to the intricate detail of a falcon’s head feathers—are without equal. His art won numerous awards, including those of AGTA’s prestigious Cutting Edge competition every year between 1995 and 1999. Roberts’s work has been displayed worldwide, including exhibits at the Carnegie Museum of Natural History in Pittsburgh, the Lizzadro Museum of Lapidary Art in Chicago, and the White House. It also has appeared in various private and corporate collections. His life and art have been featured in such international publications as JCK, Modern Jeweler, Jewel Siam, and Lapidary Journal.