Think of quartz and words like “commonplace” and “abundant” come to mind. That any member of this rather broad gem and mineral family could be a rarity of keen interest to connoisseurs and collectors (not to mention designers and manufacturers) seems incongruous or far-fetched.
Yet Mike Pirtle had the good fortune to be witness to the discovery of just such a quartz variety during a hunting trip to the Mojave desert, at a spot 100 miles north of Los Angeles, in 1987. At the spot, he confesses, he knew nothing about gems. Luckily, his companion, seasoned rockhound Bill Nicks, did. So when by chance Nicks saw an outcropping of a slightly grayish violet-blue rock unlike any he’d seen before, he knew instantly that it was rare.
Since debuting the unique chalcedony dubbed “Mojave Blue,” at the Tucson Gem and Mineral Show in 1989, Nicks, with occasional help from Pirtle, has made mining and marketing this material his life’s calling—despite sparse yields and slender (maybe a decade’s worth) reserves.
While some quartz deposits yield material in the tons, Nicks’ is good for only a couple hundred pounds per year. Of this, just 5% lends itself to high-grade cabbing and carving. Less than 1% is facetable.
Such yields may be the norm for other species, but they are slim pickings for a quartz—even blue chalcedony. Nevertheless, this production is enough to have summoned swift and widening attention for this gem. For whatever Mojave blue lacks in quantity, it more than makes up for in quality. Indeed, dealers familiar with this California chalcedony say it is the best of the breed, challenged only by a more plentiful bluer material from Africa. What makes the Golden State’s version No. 1?
A Special Sheen
The winter 1990 issue of Gems and Gemology gives Mojave Blue a small write-up. “The material has an appearance unlike anything we have previously seen in chalcedony,” the article notes, a reference to what it calls “a weak to distinct adularescent effect.” Usually associated with moonstone, a feldspar, adularescence is a silvery-white to lightly bluish, seemingly floating sheen produced by light reflections from layered inclusions. Often this sheen seems like a milky pool of light suspended in the stone.
We don’t want to overplay the so-called adularescent effect of Mojave Blue, especially since we don’t feel the stone’s beauty or success depends on it. Although noticeable in cabochon stones that we saw, it was never as strong as it is in fine moonstone. Indeed, Gems and Gemology describes the chalcedony’s sheen as “a scattering of light” possibly produced by “extremely fine, fibrous inclusions.”
Perhaps the more pronounced sheen of fine moonstone is the result of the contrast between it and its deep sapphire-blue body color. No matter how lovely, top-grade Mojave Blue does not have the deep tone and color saturation of top-grade moonstone. Instead, top-grade Mojave blue stones boast light to medium tones and more delicate saturation. Especially attractive are their violet tinges. Fine Mojave Blue and moonstone share similar degrees of translucency.
New World vs. Third World
What Nicks calls “Mojave Blue” refers to stones from his find only. This trade term could cause confusion since other deposits of blue chalcedony have been found from time to time in Oregon and Washington. In fact, Tiffany’s, the greatest champion of American gems ever known, toyed with the idea of promoting a West Coast-origin blue chalcedony around 1910-1911. Why the plan was abandoned is not known.
Anyhow, it is believed that the material the retailer wanted to market came from Oregon. If reminiscent of the blue chalcedony mined there in recent years, it would have had a stronger component of pink than Mojave Blue, says dealer James Alger, Manchester, N.H., who keeps one of the largest stocks of blue chalcedony in the country.
Unfortunately, Oregon and, for that matter, Washington blue chalcedony are even more limited in supply than their California counterpart. To find significant output of blue chalcedony, Alger says, you must rely on Namibia and Turkey.
That wouldn’t be so bad if the material from these sources was as good as that from Africa. “The Turkish variety is more grayish-blue, that of Africa more purplish,” Alger comments. “Both tend to be more opaque than the American variety.”
Even so, Alger buys a lot of African and Turkish rough, which he has cabbed, carved and occasionally faceted in Idar-Oberstein, Germany. “I can’t begin to meet the demand for American blue chalcedony,” he says. “It has begun to catch on with manufacturers and designers.”
You can also add carvers to the growing list of U.S.-origin blue chalcedony users. One of the most prominent of them in this country, Michael Dyber, based in Rumney, N.H., counts himself among the biggest aficionados of this quartz, the California variety in particular. Nicks alone has commissioned several pieces from him—one which is featured in our photo for this gem.
Blue chalcedony has certainly benefited from the growing popularity of ornamental gems in designer and custom jewelry. Well-known designers like Minneapolis-based Patrick Murphy have incorporated this gem into many pieces—often in combination with other voguish quartzes such as drusy quartz.
The choice makes good sense. Priced more affordably than, say, chrysoprase (a quartz that resembles jadeite), blue chalcedony strikes us as a bit of a bargain—given its scarcity in better grades.
True, quartz strandbys like black onyx and carnelian are generally far less expensive. But they should be since they are so plentiful. On the other hand, you should find blue chalcedony lower—or at most the same—in price than, say, non-quartz stalwarts such as lapis lazuli and turquoise.
According to Alger, expect to pay between $10 and $50 per piece for standard-size square, triangular and round blue chalcedony cabochons. However, increasingly voguish stones with very high domes could run as high as $100 per piece. You can look forward to seeing blue chalcedony in a whole raft of new cabochon cuts—as this form of cutting continues its renaissance.
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 7.95-carat blue chalcedony shown in the header is courtesy of Mojave Blue, Bakersfield, Calif. It was carved by Michael Dyber, Rumney, N.H.