Gem News International Gems & Gemology, Spring 2015, Vol. 51, No. 1

Rare Stones In Demand


Sphalerite
Brightly colored sphalerite is one of the most popular “unusual” gems sold by Coast-to-Coast. Photo by Duncan Pay/GIA; courtesy of Coast-to-Coast Rare Stones International.

For Brad Wilson and John Bradshaw (Coast-to-Coast Rare Stones International, Kingston, Ontario), their inventory of corundum and other familiar gemstones never makes the trip to Tucson. Instead, their showcases are filled with rarities such as afghanite, bastnaesite, beryllonite, clinohumite, celestite, hambergite, magnesite, montebrasite, pargasite, sphalerite, violane, and zincite. These stones often are soft and near-colorless and have cleavage, making them less desirable for jewelry. But for a collector or a designer looking for the unusual who understands how to work with such challenging stones in jewelry, Coast-to-Coast at GJX is a worthwhile destination.

Coast-to-Coast Rare Stones International
In his interview, Coast-to-Coast’s Brad Wilson explains that rare gems have a place in jewelry, too. Innovative designers seek out rare materials such as sphalerite, sphene, apatite, and even afghanite for clients who appreciate the unusual.

Some of the lesser-known stones available at Coast-to-Coast included datolite, cobaltocalcite, faceted aragonite, and tenebrescent scapolite. Fluorescent opal was a noteworthy new find. Under ordinary interior lighting, this opal is near colorless to very pale yellow. It can fluoresce bright green in response to the small UV component in ordinary daylight. Placed under an ultraviolet light or 405 nm laser, the fluorescent effect is spectacular.

With unfamiliar collectors’ stones, colorful varieties usually sell best. Wilson’s more popular items for this show included sphene, sphalerite, and apatite. He told us that other stones rise and fall in popularity. One example is tugtupite, a rosy-pink mineral, usually found in aggregate form, that exhibits both interesting fluorescence and tenebrescence. It sold out on the first day in previous shows, according to Wilson, but in 2015 only a few had sold by the third day.

Donna Beaton is colored stones technical advisor for content strategy at GIA.