Roland Piquepaille writes "In 'The many facets of man-made diamonds,' Chemical & Engineering News (C&EN) writes that synthetic diamonds are getting bigger and cheaper. An example: for Valentine's Day, you can buy a yellow colored man-made diamond, visibly indistinguishable from a natural one, for $4,000 per carat. This is a 30% discount when compared with a natural diamond. This very long article also says that if synthetic diamond makers are targeting the jewelry market first, these new products will have an impact on many other industries. Not only is it now possible to grow bigger diamonds, you also can choose their color. 'Colored diamonds, which are valuable and very rare, can be created by introducing carefully controlled elemental impurities into the stone,' says C&EN. For instance, nitrogen produces a yellow stone. Infusing boron into the growing diamond produces a blue gem. This overview contains some details, references and photos of men-made diamonds, but read the original article for even more technical explanations if you have the time."