And to be perfectly clear, synthetic diamonds are in every sense real, actual diamonds, chemically identical to the things that de Beers tries to get you to buy (except that the synthetic ones are usually higher quality). They are not to be confused with simulated diamonds, which are other materials which happen to superficially resemble diamonds (cubic zirconia, quartz, cut glass, etc.).
Last time I looked, I got the impression that there was a limit to the size you could get in a lab, and it was impossible to get a white diamond. The synthetic sellers also seemed very reluctant to discuss the clarity of the synthetics.
What’s the current state of the art in the four C’s?
I think I saw that movie. It didn’t end well for… well, everybody.
I don’t think there’s any upper limit to size with vapor deposition-- You just have to be more patient. If there is an upper limit, it’s large enough not to matter, since I’ve seen synthetic gem-quality colorless diamonds the size of golf balls, and while there are a few natural ones that size, they’re hardly what one could consider on the market.
I’m still in awe of the high temperature high pressure method. To put the earlier numbers in more picturesque terms, imagine one of the largest, heaviest diesel locomotives working today. Then imagine two of them, and their entire weight concentrated on one square inch. And then the thing being thus squeezed being heated to a temperature much hotter than molten iron. And then being left that way for six to nine months! This is truly geological type stuff, not your ordinary wine press! 
In Arthur Machen’s short story, The Inmost Light, the protagonist captures his wife’s soul in a synthetic opal of great size and beauty. The results for her were… not good.
The joke on sci.chem a decade ago when this LifeGems story broke was to hurry up and start feeding grandma carbon 13, then after the LifeGems process, you can see how much of a positron emitter the gem made from her was. Or wasn’t if you doubted the process.
Aren’t all industrial synthetic diamonds yellow? Something about nitrogen contamination …
I would have to question the veracity of the Wikipedia quotes. Since 50 1-ct diamonds would weigh exactly 10 grams, the losses from the extraction and purification process are zero?
Even if we accept the zero loss through processing, using Fear Itself’s estimate of 5 Lbs of cremated remains, 10 grams of carbon would be 0.44%, more than the Magnesium content (which is reported), so I suspect very low carbon content. Furthermore, per Fear Itself’s cite,
Emphasis mine.
While I will accept that there is some carbon in cremated remains, this site reports that it is truly only a trace amount
So it would appear that there is carbon in the cremated remains, but very little.
Actually, synthetic gem quality diamonds are identified as being too perfect. That is, they have clarity and brightness that exceed the highest quality natural diamonds. It is true that they do make synthetic industrial diamonds (there is a facility in Arkansas, I believe), but they intentionally introduce impurities to keep them from being gem quality. That is, they make an extra effort to prevent them from being gem quality.
The early pressure-generated “cultured diamonds” were yellow–but still pretty and clear–but at least in theory the color issue can be overcome at some expense.
The ones made by the other method I’ve heard of, which I guess was vapor deposition, were absolutely perfect. DeBeers soon declared that what we were supposed to want were natural diamonds with flaws. :rolleyes:
I guess sparklie-warkily isn’t important cutting concrete, just so the diamonds are hardest.
I wonder if you could encase a set of chromosomes in a diamond, as a cheap alternative to cryogenics?
Obligatory Vodka advert.
And you can thank DeBeers for that.
Okay, that was… a thing, I guess. But at least now I think I know where Jim Theis got his ending for The Eye of Argon.
In return, I offer you Bob Shaw’s The Light of Other Days. Only very tangentially related to the topic, but a short story about “slow glass” – glass that slows the speed of light so enormously that it retains visions of the past. Shaw wrote two other stories on the same theme and then later a sort of novella that tied them all together.
Natural diamonds are the most valued as gems, but that’s entirely due to propaganda by de Beers. But then again, the value of diamonds as gems at all is almost entirely due to that same propaganda. Natural diamonds aren’t nearly as rare as they’re made out to be.
Sounds like having to walk to school uphill both ways. (Shakes cane) “In my day, missy, I had to scrub the sink before and after I died!”
Personally, I refuse to do any housework after my death.
I remember that story, but had forgotten the name. Thanks!
Did you know that this whole process was filmed over half a century ago?
Diamonds aren’t rare at all. If they were especially rare, they wouldn’t be advertised to the masses as they are. Diamonds are supposed to be the hardest gem. They represent durability.
Of course, even that is kind of sillly. The difference is hardness between a diamond and a sapphire is an academic distinction most of the time.