Synthetic Diamond

The largest gem diamonds grown by G.E. are about a carat, and stones of about carat in weight have been cut from some of Chem. These diamonds are as hard and dispersive as natural gems. They are true diamonds, not imitations. But the cost of manufacture is so high that even in these small sizes synthetic diamond cannot compete with natural diamond on the gem market. This situation might easily change with new technological developments.

Synthetic Ruby and Sapphire
Ruby and sapphire have long been considered two of the most desired¬ and valuable gems. Natural material has never been available in sufficient quantity to meet world demand. It is therefore not surprising their synthesis would be considered a worthy goal. The earliest experiment were those of Marc Gaudin in France in the mid-19th Century, although gem quality corundum was not produced. In the mid 181¬however, rubies appeared on the gem market that were initially thought, to be natural, but which careful study showed to be manufactured ¬products.

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Many of these rubies, known as "Geneva rubies," because it was thought that they were made near Geneva, Switzerland, were sold as natural. Just after the turn of the century another type of ruby peared on the market. Termed "reconstructed ruby," this material .. supposed to have been made by melting together bits of natural ruby. In recent years it has been demonstrated that such a process will not work ¬so these rubies must also have been synthesized from chemical raw. materials.