If pyrite is known as “fool’s gold,” then rock crystal—the clear, colorless variety of quartz—could be called “fool’s diamond.” Certainly, rock crystal fooled experts for a very long time. And explaining the differences between rock crystal and diamond kept scientists of antiquity busy. Here’s what they wound up saying and the gem world kept believing—that is, until the dawn of modern chemical analysis.
According to Ann and Si Frazier in the April 1992 Lapidary Journal, the ancients divided colorless gems into two types: ripe and unripe. You can guess which was which. Ripe gems were diamonds and unripe gems were crystal quartzes. The distinction was based primarily on origin. Had the latter, it was theorized, grown in the warmer climes of the East, they would have “ripened” into diamonds. But having grown in the harsh, cold climes of the West, quartzes were victims of arrested development.
Actually, unripe gems weren’t just quartzes—just as ripe gems weren’t always diamonds. The two categories encompassed a slew of species, including topaz, corundum and beryl, that were classified as either adamas (indestructible) or krustallos (ice-like), depending on origin. Indeed, it was widely believed—even by the likes of such eminent ancients as Theophrastus on Athens, a naturalist who wrote the earliest-known treatise (an gem, “A History of Stones,” circa 315 B.C.) and Pliny the Elder (the Roman follow-up who wrote the second-oldest study on gems circa 50 A.D.)—that crystal was once frozen so solid it couldn’t thaw. Hard as crystal was, it still was no match for adamas.
Thus rock crystal as a gem was the poor man’s diamond. But as a material, it was the rich man’s glass, used during the Middle Ages and the Renaissance to make vessels and containers often so “beautifully engraved with pictured figures as to be transformed into veritable works of art,” wrote gemologist Max Bauer in his 1896 book, “Precious Stones.” As glassmaking came onto its own, he continued, “the art of working rock-crystal became forgotten, for it was soon found that vessels equally transparent and finely finished could be made in glass with much less labor.”
But, excepting amethyst, rock crystal was the most important quartz family member for considerably more than a millennium. This stature is confirmed by visits to the Prado Museum in Madrid, Spain, and the Rijks Museum in Amsterdam, the Netherlands, “where,” says Si Frazier, “entire galleries are devoted to masterpiece of Renaissance art in the form of carved and engraved Alpine rock crystal.” But if Europe isn’t in your travel plans, visit the annual Tucson Gem Show where displays of works by a new generation of gem carvers, including Susan Allen, Tom McPhee and Howard Fielder, suggest the greatest resurgence of rock crystal artisanship in centuries.
A Natural Substitute
Anyone familiar with the history of diamond production would know that many so-called diamonds worn in the West until the discovery of Brazil’s diamond deposits in 1725 were likely rock crystal quartz from the Alps. Only the flood of stones from South Africa’s mammoth diamond mines in the early 1870s finally began to alleviate the need for quartz as a substitute.
Until then, rock crystal had served as one of the better and most readily available diamond stand-ins—so effective as such that when the Hapsburgs of Austria ruled Belgium between 1477 and 1792 they outlawed mining of rock crystal. No wonder, then, that some experts call rock crystal “quartz-diamond.” The most famous of these quartz-diamonds is rhinestone. “Originally,” notes Frazier, “they were called ‘Rhine diamonds’ because they were cut from pieces of Alps’ rock crystal washed down the Rhine river.”
This revelation about rhinestone is just one of the many important discoveries Frazier and his wife made while compiling a landmark lexicon of quartz-diamond terms for Lapidary Journal that was published in two parts in April 1991 and 1992. To gather this exhaustive list, the Fraziers combed 18th and 19th century mineralogical dictionaries and found them studded with scores of such terms.
Seen in somewhat paranoid perspective from our own time when jewelers are routinely conned by cubic zirconia (the most popular man-made diamond simulacant in history), one might at first be tempted to find the profusion of synonyms for rock crystal like “bastard diamond,” “mock diamond” and “soft diamond” evidence that jewelers in the past had to be continually on guard against this remarkable diamond substitute.
Doubtless, rock crystal lent itself fraud. But the link between diamond and quartz can also be viewed as a legacy that stretches thousands of years. Even today, local quartzes in a wide variety of places from Alaska and Hawaii to Colorado and New Jersey are called “diamond”—not just to deceive but, we suspect, to make what is by now a reflexive association between the two. After centuries of living in the diamond’s shadow, any marketer for rock crystal worth his salt must take advantage of this quartz’s strong resemblance to diamond.
How grand it would be if some day, as happened with tanzanite and tsavorite, gems which started their careers as sapphire and emerald substitutes respectively, rock crystal as a gem earned respect for what it was—not what it wasn’t.
But it has had few to champion it as a gem in its own right. Bauer, the most notable of rock crystal’s defenders, wrote, “[Rock crystal] stands out prominently among all other minerals by reason of its clearness and transparency, in which respect it often surpasses even the diamond, although it is not comparable with the latter in lustre or play of colors.”
Bauer’s praise for rock crystal may give us moderns pause for thought, but it probably struck the more enlightened of his contemporaries as common sense. Even today, there are dozens of localities whose main claim to fame is the fact they are rich in quartz-diamond. Every year, thousands of rock-hounds and tourists flock to New York’s Mohawk Valley in Herkimer County to prospect for what Frazier describes as “sparkly quartz crystals” known as “Herkimer diamonds.”
If rock crystal ever regains widespread public appreciation… it will again be in the domain of artisanship and art. The thriving commerce in exceptionally large and clear quartz crystals from Brazil and Arkansas attests to the full rebirth of quartz carving—with one big difference. North America’s and Germany’s new breed of quartz carvers are a far cry from the artisans of old. Instead of making decorative objects and statues notable for their craftsmanship, these new crystal workers see themselves as visionaries. Perhaps as rock crystal sculpture gains acceptance, it will finally come into its own as a gem. Cross your fingers.
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 rock crystal quartz sculpture shown in the header image is courtesy of the Susan Clark Gallery of Gem Art Inc., Vancouver, British Columbia. It was carved by Thomas McPhee.
