Dealers don’t like to admit it but blue topaz has given aquamarine, its blue beryl double, a hard time in the last few years. Indeed, lighter-shade aqua that once fetched $150 per carat has dropped considerably below $100 per carat because look-alike blue topaz was selling readily to the trade for $4 per carat. Manufacturers who couldn’t see any difference between the two stones but price took topaz. So did retailers, especially when they realized that, for $8-$10, they could buy all they wanted of deeper-shade blue topaz that rivaled $200-$400 per-carat aqua in color intensity.
As a result, a lot of U.S. aqua sellers have had to add blue topaz to their inventories over the last few years. They were joined by hundreds of dealers all over the world racing to ride the huge wave topaz wave to America’s shores.
And what a blue it has been. Indelible as it may seem, blue topaz has become the biggest selling non-traditional colored stone in this country. But while the gem has also scored big abroad, passion for it in foreign markets hasn’t been able to cripple aqua sales as it has done here. Dealers believe that consumers in sophisticated gem-consuming countries like Japan clearly see irradiated blue topaz as a novelty and not as an aqua substitute. In America, however, it is regarded as a full-fledged gem. But with the market virtually flooded, and prices continually dropping, demand for blue topaz may have flattened.
Whatever the future for irradiated blue topaz, many gem importers who sell it will remain ambivalent about the gem, stocking it, without much enthusiasm, to accommodate customers. Granted, these dealers admit, the stone gives the look of fine aquamarine at a fraction of that gem’s price. But the fact that topaz color is produced at will using irradiation riles them. Somehow this makes the gem more a product of the laboratory than nature.
Trade ambivalence about topaz is evident in the marketing and merchandising of the gem. Few retailers even bother to tell the public that the blue topaz it is buying by the ton owes its color to a nuclear reactor or a linear accelerator.
Some see such non-disclosure as a coverup of radioactivity health hazards. Not so. Interviews with treaters, dealers and government officials lead us to conclude that blue topaz poses no danger whatsoever. First of all, stones treated in ways that leave residual radioactivity are quarantined (usually anywhere from three months to one year) until levels read ultra-conservatively low. By the time these stones get to jewelry stores, radioactivity is unmeasurable with conventional geiger counters. And even when the Nuclear Regulatory Commission (NRC), which licenses reactors in this country where topaz is treated, ran radioactivity tests of irradiated blue topaz using ultra-expensive and sensitive measuring devices, it found no cause for concern.
So why neglect to tell the public about irradiation? The answer, we think, lies in the fact that the gem is a high-tech hybrid that transcends all conventional classifications. On one hand, the stone is natural, starting life as super-abundant colorless or tinted topaz from places like Brazil and Sri Lanka. On the other hand, its color is entirely manmade, due to a combination of irradiation and heating.
Now topaz isn’t the first gem to be safely and permanently colored by irradiation. Diamonds have been subjected to this process since the late 1940s. What is new about irradiated topaz is its affordable profusion and its phenomenal success. A decade ago, when irradiated blue topaz was still a relatively new market entry, wholesale prices were around $40 per carat to bulk users. But today for the same volume buyers are charging well little as $2 per carat for light to medium tones, a few dollars more for deeper tones. The reason: over-saturation of the marketplace. That surfeit, one that dealers liken to the Linde synthetic star sapphire craze of the 1950s, has aroused predictions of a topaz bust.
Birth of the Blues
Blue topaz specialists resent the comparison of their product to the Linde star. They remind critics that aquamarine, the stone blue topaz resembles so strongly, is heated to remove green. But decent aqua doesn’t cost under $10 per carat. Nor is it available in anywhere near the quantity of blue topaz. Last, exposure to low-level heat is a far cry from exposure to electron and neutron bombardment.
Nevertheless, while blue topaz is as much the creation of a lab as the Linde star, it is exhibiting more staying power. Further, dealer annoyance with the gem seems somewhat groundless. Those who complain that blue topaz has a mass-produced color sameness possible only with irradiation are probably not aware that only 20% to 30% of the stones irradiated turn a desirable color. True, the eye-shadow names like “sky blue” given to irradiated topaz hues suggest paint-chip color consistency. But such topaz, specialists assure us, is not the case. Instead, these terms are market shorthand for various irradiation techniques used.
Treaters who want deep aqua-blue colors use neutron bombardment in a nuclear reactor and market the final product under the name “London blue.” Neutron treatment is the only means by which to produce smaller calibrated stones with deep color. If this technique is used, stones fall under NRC jurisdiction. Current NRC rules require that neutron bombardment done in this country, regardless of gem species, be performed only by NRC-licensed reactors. If stones are reactor-treated abroad, their U.S. importers must be licensed by NRC to do so.
However, blue topaz irradiated in any manner other than neutron bombardment escapes NRC scrutiny. That’s because other techniques involve non-residual radioactivity for which measuring decay (or half lives) is not important. After neutron bombardment, the most common irradiation technique used to color topaz is electron bombardment in a linear accelerator.
More recently, topaz producers have combined reactor and accelerator treatment to produce an attractive color we find reminiscent of blue zircon, a stone that owes its color to heating. Ironically, several importers told us the color of these stones was “fake.”
Treaters think this reaction is more psychological than aesthetic. They note that tanzanite, a brownish-purplish zoisite heated to turn a desirable blue, is almost never found naturally in its blue state. So what’s the difference between browning zoisite and colorless topaz? Except for price, it’s looking more and more like there isn’t any other answer to that question.
Please note: this profile was originally published in 1988 in Modern Jeweler’s ‘Gem Profiles: The First 60’, written by David Federman with photographs by Tino Hammid.
The 60-carat irradiated blue topaz shown in the header image is courtesy of Overland Gems, Los Angeles.