Twenty-eight years after it was discovered in 1868, gemology pioneer Max Bauer wrote that demantoid garnet would probably never earn full-fledged gem status. Much as he admired the stone, Bauer thought it was too small, soft and scarce to merit anything more than curiosity.
Just about the same time, the late 19th century’s other great gemology pioneer, George F. Kunz, was in the Ural Mountains of Russia, demantoid’s prime source, buying every piece of demantoid rough he could find. Kunz, on leave from Tiffany where he served as the store’s chief gem buyer, was financed by banker/tycoon J. Pierpont Morgan, an avid gem collector.
For more than a decade, Kunz had been a devotee of the Russian green garnet, so much so that Tiffany made more extensive use of the gem than any other jeweler of the age. Indeed, demantoid was as closely associated with Tiffany in the late 19th century as tsavorite, a distant-relative African green garnet discovered in 1971, is with Tiffany in the late 20th century. True, demantoid was a darling with upper crust English and French jewelers. But the gem owes much of its passionate popularity with connoisseurs today to the Tiffany mystique—despite the fact that it has been at least 65 years since the last significant production of Ural Mountain demantoid.
Thanks to Kunz, demantoid achieved, and still retains, an importance far disproportionate to its availability. “Maybe one in every 100,000 pieces of Victorian jewelry used demantoid”, says noted gem and jewelry historian Joseph Gill. Gill and Shortell, San Francisco. “Yet you’d never think how little of the stone actually was with all the fuss they make about it today.” Why? The gem’s name gives a clue to the cognoscenti’s lingering love.
Dispersion greater than diamond
Almost all garnets are plagued by very low dispersion. But demantoid, a member of the andradite family, is blessed with more of this attribute than even diamond, a stone prized for its dispersion. No wonder then, that the garnet’s first sellers named it demantoid (meaning diamond-like), after the Dutch word “demant” for diamond. (Why a Dutch word? The name was still the garnet’s principal diamond-cutting center at the time the garnet first came on the market). And demantoid’s fiery brilliance gave the stone, usually found in small sizes, a decided edge over lesser-luster emerald and peridot, the worlds leading green gems. Indeed, Gill says, demantoid was often sold as “olivene” or “Uralian emerald.” That is why many pieces of Victorian jewelry made between 1885 and 1915 feature demantoid.
Luckily for demantoid, America and England had fallen under the heavy spell of Darwin-inspired naturalism. The resulting fascination with brute nature manifested in jewelry design as a voguish use of bird, fish, flower and reptile motifs. Since green symbolized nature, jewelers gravitated toward emerald. However, motif pieces consisted largely of melee and, as said earlier, demantoid was the green melee stone of choice among the knowledgeable.
No doubt, larger demantoids would have figured as pro- minently in late 19th century jewelry, only supply prevented it. The stone was very rare in sizes over 2 carats. The largest specimen we were able to see when researching this article was a magnificent 8-carat stone in the private collection of New York dealer Ralph Esmerian, R. Esmerian Inc.
Overemphasizing ‘horse-tails’
Demantoid garnet is probably the only gem whose inclusions are considered an aesthetic property, as important as color and brilliance. Believe it or not, the value of a stone depends heavily on the prominence of what are called “horse-tail” inclusions (bundles of byssolite—a form of asbestos—that spray out in a curve from a central chromite crystal).
One reason for the fuss over horse-tail inclusions is that they are thought to conclusively prove Ural Mountain origin. Well, think again. According to Gill, “A few demantoids with horse-tail inclusions have been found in Ceylon and the Belgian Congo. So you’ll need more than a horse-tail to confirm Russian origin.”
Gill’s statement will come as a shock to the many collectors who believe a horse-tail is prima facie evidence of a Russian birthplace. “A large part of demantoid’s magnetism,” Gill continues, “is its Ural heritage. These mountains also produced small amounts of alexandrite and emerald, the best of which epitomize these species. Hence the collective aura of Ural Mountain gems. To suddenly find out that one’s Ural Mountain demantoid may have come, instead from the lowly gem gravels of Ceylon is like being told one’s Burma ruby really comes from Thailand.”
The letdown is even worse with demantoids from Italy, Czechoslovakia, Arizona and, more recently, Mexico. For starters, most of these stones are so yellow (the result of iron as opposed to chromium coloring) that they should perhaps be called topazolite, a greenish-yellow andradite. Often highly included, these mostly unappealing stones lack the one inclusion that matters: the horse-tail.
Demantoid vs. Tsavorite
To traditionalists, there is only one kind of green garnet worthy of praise: Ural Mountain demantoid. A newer generation, however, thinks that tsavorite, an East African green grossular garnet, is as praiseworthy. The argument resembles that between fanciers of Colombian versus those of Zambian emerald. Fine demantoid garnets, like fine Colombian emeralds, tend to have a sweet- er, livelier color, with preferred tones a bit lighter than those of their African counterparts. But the greater gravity of tsavorite color, like that of African emerald, has become much less of a drawback to acceptance.
Where tsavorite has a clear edge over demantoid is with hardness (7 on the Mohs scale for tsavorite, 6½ for demantoid). That half a point difference may not seem like much, but it translates into a decided durability edge for tsavorite. This helps explain the preponderance of garnet brooches and pins in estate jewelry. Demantoid’s softness made it unwise for use in rings; however, the lack of large sizes also contributed to a paucity of demantoid ring stones.
At present, demantoid has a strong following among collectors, and fine stones between 1-2 carats fetch up to $2,000 per carat from dealers. “So if you buy an old piece with bright green stones in it,” advises Gill, “don’t dismiss them as peridots or tourmalines, If demantoid, the value of the piece could jump considerably.”
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 3.47 carat demantoid garnet shown in the header image was courtesy of Echo Gems Inc., Scottsdale, Ariz.
