Dog-Tagging Diamonds

When police recover a stolen auto or camera, they can attempt to find the owner through the item's serial number. But when authorities find filched gems, they know the owners have probably kissed their property goodbye. Most gems contain no traceable markings. Systems for registering diamonds by photography and other means have proved unreliable. Says Robert Doubet, vice president of Lazare Kaplan & Sons, a New York City diamond-cutting firm: "Once removed from its mounting, a diamond is as good as ownerless."

Lazare Kaplan has now developed a way to dog-tag diamonds. It has patented a device that uses a laser beam to inscribe gems with a trademark and seven-digit number that is visible only under magnification. The company spent ten years developing the desk-size engraving device, which, it says, performs the delicate operation without affecting either the clarity or the color of the stones. The firm has leased one of its first six machines to a Japanese company and three of them to Manhattan's Gemological Institute of America, which will inscribe stones for jewelry retailers. Says the institute's Burt Krashes: "Anyone caught with a laser-inscribed stone would be a dead duck." The typical cost for the owner of a one-carat stone is about $110. Since a flawless diamond of that size runs anywhere from $5,000 to $25,000, a girl's best friend may soon be the marking on her stones.