Back in 2003, I posted an entry pointing to a Wired article about synthetic diamonds. (I also linked in passing to the seminal 1982 Atlantic exposé of De Beers and the diamond industry, "Have You Ever Tried to Sell a Diamond?")
Well, De Beers is still going strong, alas, but at least it's now possible to get lab-grown diamonds that look good enough (to the untrained eye, anyway) for use in jewelry. An acquaintance of mine has posted the story of how he and his then-fiancée (now wife) put together an "Engagement Ring With Only Lab-Created Diamonds," complete with links, a bunch of photos, and even a brief video showing the ring sparkling in the sunlight.
Well worth reading if you have any interest in using lab diamonds for your next piece of diamond jewelry. Sounds like it was a pleasant experience all around, and avoided many of the political issues associated with ground-grown diamonds.