When in 1981 the gem trade got wind that ametrine, a combination of amethyst and citrine, could be concocted in the lab by heating and irradiating the warm welcome it had given this gem a year earlier became a cold shoulder.
The swift reversal of fortune for this purple-yellow quartz made sense back then when revelations of what by current norms seem benign treatments still had considerable shock value. But continued ostracism isn’t justified more than 10 years later. After all, it’s kid’s stuff gemology today that when you heat amethyst, you get citrine (indeed, nearly all citrine is heated. So if folks) and when you irradiate citrine, you get amethyst. So it follows that if you perform both heating and irradiation with either amethyst or citrine, you can get zones of both in one stone.
But at the turn of the last decade, when gem treatment was considered more as hanky panky than enhancement, the mere rumor of such, particularly irradiation, would have been enough to kill sales of something as exotic as ametrine. This is what happened to this stone when it suddenly appeared in profusion at the 1980 Tucson Gem Show. Leading gemologists at once began to question its origins. A year later, after author Kurt Nassau demonstrated that ametrine could easily be created in labs, a traumatized trade shunned the quartz. No matter that Nassau’s case was based on supposition rather than hard proof. The mere chance ametrine came from a lab was evidence enough.
The trade has itself to blame for the gem’s nose dive. From the start, ametrine was sold as a fluke of nature, found at one locality. Yet when pressed for its exact whereabouts, dealers gave conflicting answers. “I was told the gem came from Brazil, Uruguay and Bolivia,” Nassau, an expert on gem treatments and synthesis, remembers. “When a gem with one source suddenly has three, that means either people are trying to keep its real source a secret or there is no source and the material is created synthetically or through treatment.”
Nassau, who had bought a man-made purple-yellow quartz 15 years earlier, already had strong suspicions about ametrine. The failure to get straight answers about its origins only deepened his doubts. “I decided to see if I could create bi-colored quartz in the lab,” he continues. “Within a matter of weeks I was able to do so using a variety of techniques (heating, irradiation or sometimes both).”
Right after Nassau published his findings in 1981, the fledgling market for this gem collapsed like a souffle. Prices for free and calibrated sizes which had spanned from $6 to $30 per carat toppled to between $2 and $10 per carat—their levels today more than a decade after the debacle. For a while, ametrine seemed destined for the same gemological infamy as maxixe (pronounced “ma-shi-shi”) beryl, a quick-fading cobalt-blue irradiated beryl sold as aquamarine in the early 1970s. Now this two-in-one quartz is staging a comeback, in part because it is championed by some famous gem sculptors, including Germany’s Bernd Munsteiner.
Allaying Fears
In a world where heated gems like tanzanite and irradiated gems like blue topaz have become jewelry store staples, consternation over possible lab origins of ametrine’s colors seems pointless and passé, especially since those colors are permanent. Besides, many gemologists who once suspected the gem of being treated, now concede that some of it may be natural. Nassau is even saying so publicly.
Yet, as if reacting to still-fresh charges of trickery, dealers like Ray Zajicek of Equatorian Imports, Dallas, feel compelled to defend ametrine against accusations of hoax. “Hell, at current prices, it hardly pays to mine it, let alone treat it,” he cracks. “That’s one reason why you don’t see too much ametrine around lately.”
Okay, maybe the economics of the current market discourage dealers from producing massive quantities of ametrine in a lab. The question remains: Was any of the original ametrine that came on the market in 1980 treated? Zajicek, who bought ametrine rough when it first came on the market, is convinced it wasn’t. “The cost of treatment is based on weight,” he explains. “So if a kilo of uncut ametrine typically yields 30% clean material, why would anyone pay all that extra money to treat the rough?”
Gem sculptor Munsteiner shares Zajicek’s faith in ametrine’s all-natural status. Just to be sure, he uses only rough that he himself buys at the gem’s one source in Bolivia near the border with Brazil. As a result, Munsteiner has been a staunch advocate of the gem ever since he first started working with it in 1981. It is eyewitness testimony such as his that has persuaded skeptics that at least some ametrine is legitimate.
However, for the sake of argument, let’s say ametrine owes its color in part to irradiation. Given laxer attitudes today toward freely irradiated gems, it seems silly to fault treatment for the trade’s continuing indifference to ametrine. Clearly other factors play a role.
Art vs. Adornment
While depth of ametrine color which often combines popular green with equally popular red, ametrine combines popular blue-colored less popular brown and yellow. To make things worse, at the time ametrine was introduced, citrine had little of the popularity it enjoyed in the 1930s and 1940s or has since begun to enjoy again.
On top of this, demand for citrine was then narrowly focused on its deep brownish- and reddish-orange coco colors. The gem’s lighter-toned yellows and golds were not nearly as appreciated as they are today. Since these latter hues were mostly what one saw in ametrine, the stone struck many jewelers as bland. So even without the taint of treatment, ametrine might well have bombed.
What ametrine needed to arouse interest was cutting as novel as its appearance. This is why ametrine has proved so endearing as a candidate for the free-form, or fantasy, cutting that has found a wide acceptance recently. This cutting style heightens the gem’s wonderful color contrast.
Nevertheless, ametrine seems to reverse its most striking effects for stand-alone gem carvings. It just may be that this bi-colored quartz is better for art than for adornment. So thinks one of Munsteiner’s main American distributors, James Alger, based in Manchester, N.H. “As a jewelry stone, ametrine is rather uninteresting,” he says. “But use it for carving and its fullest potential for color interplay is realized.”
Please note: this profile was originally published in 1992 in Modern Jeweler’s ‘Gem Profiles/2: The Second 60’, written by David Federman with photographs by Tino Hammid.
The 31.26-carat ametrine shown in the header image was courtesy of James Alger Co., Manchester, N.H. It was cut by Bernd Munsteiner.
