Lab-Made Diamonds Just Like Natural Ones

Sept. 9 -- Two small companies say they are taking a quantum leap forward into a new diamond age.

Apollo Diamond Inc. in Massachusetts and Florida-based Gemesis Corp. each have produced a new type of lab-made diamond that is difficult, though not impossible, to distinguish from natural diamonds.

The companies say that their manmade gems — to be sold at lower prices than natural diamonds — will be labeled so that they will not be confused with natural diamonds. But experts say that retail jewelers would not be able to tell the difference on their own.

"No chance," said Mark Yakubov, a gemologist at the International Gemological Institute in New York.

A gem lab, equipped with special equipment to separate natural from synthetic diamonds, will be able to spot the synthetics whether they are marked or not, experts say.

Mine vs. Machine

Last year, $27.4 billion in diamond jewelry was sold in the United States alone, according to the Diamond Information Center.

Natural diamonds are mined from deep in the earth. They are formed of carbon that has been exposed to immense heat and pressure over billions of years. Synthetics have the same physical properties, but they are created in a laboratory.

The new manmade diamonds from Apollo Diamond are created in a few days by a machine in an industrial park near Boston through a process called chemical vapor deposition. Diamond crystal is formed when a plasma cloud of carbon is deposited onto diamond wafers. The wafer seeds grow into diamond mini-bricks, rough diamonds that are sliced into wafers, and cut and polished into diamonds.

Apollo estimates it will be able to sell the synthetic diamonds for 30 percent less than what natural diamonds go for.

At Gemesis, which is based in Sarasota, Fla., synthetic diamonds are created through a high-pressure, high-temperature technique that mimics the geologic conditions under which natural diamonds are formed.

In a capsule placed under high temperature and pressure, graphite — a form of carbon — breaks down into atoms and travels through a metal solvent to bond to a tiny diamond seed, crystallizing layer by layer. Three or four days later, the stone that is formed is then removed from the chamber and cut and polished into a synthetic diamond.