Emeralds are a different mineral - beryl, instead of corundum. In another variant, beryl provides aquamarine.
Emeralds are a whole nother thing: Be3Al2(SiO3)6. Sapphire and ruby are Al2O3, and of course Diamonds are carbon.
I remember the article the OP mentions. One important characteristic of the process is that every new layer was a bit larger than the layer before, so the crystal was growing not only in number of layers but also the layers were bigger (in a cone or pyramid shape). This meant that they could wait long enough and make things like watch faces or screens of diamond so they would be perfectly scratch proof.
I also remember that they were making only yellow diamonds but that it was an executive decision, not a technical limitation of the process.
Also that the only way to tell them apart from natural diamonds was that they were perfect. No inclusions, or grid imperfections.
And yes, De Beers was giving out the tools needed for jewelers to spot them at a ridiculous price per unit. It seems that you average jeweler couldn’t spot them with their regular tools.
Anyways, I think that the process was extremely interesting in that it provided diamonds of dimensions previously unavailable which opened the way for truly new applications.
I think the problem (at least with me) is that in this area I am a layperson and I distinguish between synthetic and artificial. Synthetic just means “created” where artificial means “fake” or “imitation”. A synthetic diamond was synthesized or created in a lab. An artificial diamond is something that is not a diamond.
Expert jewelers who work with stones can generally tell manmade stones from natural ones, including diamonds. Sometimes they have to look at them under a loupe to tell, but not always–they are reading them, the way radiology experts read x-rays. (I can’t tell a CZ from a diamond, but if it’s large then I will suspect CZ, just because goodlooking large diamonds are rare and expensive.)
ALL gemstones used in jewelry can be enhanced by jewelers. Sapphires can be colorless, but if colored they are probably treated by heat (a permanent enhancement). Fake star sapphires are pretty obvious if you know what you’re looking for. A natural star sapphire will have a much subtler “star” than a fake, but even the natural ones will likely have been enhanced by heat techniques.
If you run into a manmade diamond or CZ that seems to cost as much, or nearly as much, as a natural mined gemstone, the cost is probably the setting. You can get really cheap jewelry with a CZ, but the “gold” will rub off the first time you wear it. CZ earrings set in 14k gold (yellow, white, or rose) will be expensive, for the sake of the setting and the jeweler’s artistry, not just for the stone.
Diamonds are graded on cut, clarity, color, and carat. The typical diamond cut is “brilliant cut” which has 58 facets, each of which is cut separately. The CZ will have the same facets. This cut, done by experts, enhances the brilliance or fire of the diamond.
Clarity–Most diamond stones that go into jewelry are a minimum of SI1 or SI2–“slightly included.” This means no inclusions visible to the naked eye (but jewelers and people who are into diamonds can see them). There’s a lot of gradings ahead of this one, and with some experience you can see that the higher grades are sparklier, hence better. The grades go up to VSI (very slightly included, 1 and 2), VVSI (very very, etc.) And F- F1 (flawless, meaning no inclusions seen by an expert with a 10x loupe).
The color ratings are D, E, F (colorless), G, H, I, J (near colorless) K, L, M (faint yellow), M-R (very light yellow). But yellow diamonds can actually be in a class by themselves–very rare, very expensive.
Diamonds are graded by the International Gemmological Institute, the European Gemological Laboratory, and the Gemological Institute of America, and they provide certificates. In some cases the IGI will have a number engraved on the diamond itself, and many diamond dealers also have an idenfication number on their stones–obviously, where it’s not visible to the naked eye but can be read with a loupe.
The Apollo manmade diamonds I’ve seen have used the same grading system, and I haven’t seen anything higher than a SI2. As far as I could tell, it didn’t look quite as good as a natural SI2, but it was somewhat cheaper.
I understand that colored natural diamonds (except for yellow and brown, black) are very rare. However, colored diamonds can be produced by neutron irradiation-can synthetic diamonds be made in colors?
Really? I had understood that the geometry of the brilliant cut was precisely calculated based on the index of refraction, so as to produce the maximum sparkle (where sparkle is measured in some objective quantitative way). Since cubic zirconia has a different index of refraction from diamond, I would have expected that it would also have a different optimum cut.
I’ve bought from here and have been very satisfied.
Might it just be the same general cut, but with different angles? I.e. there’d still be the same general arangement of 58 facets, but stretched or squished so that you get optimimum sparkliness with a different refractive index.
Rather than using “artificial” or “synthetic” (which also sometimes implies “not real”) to describe these diamonds, I’d suggest “manufactured”.
I believe that the reason that the manufactured diamonds are as expensive as the mined variety is that it’s not in the manufacturer’s best interested to get into a price war with De Beers. In fact, it’s not in any diamond producer or holder’s interest to get into a price war, because the main reason that diamonds are at all valuable is that they are (artificially) limited in supply and perceived to be rare luxury goods. As soon as the price starts dropping, everyone involved in the production is worse off. Even worse for Apollo, if diamond prices fall enough, they might see the prices for industrial diamonds fall to the point where Apollo’s main business is no longer profitable.
So both sides will continue to have high prices, and sell based on other things. Apollo will sell their diamonds as more ethical than mined diamonds, and de Beers will sell theirs as more real than manufactured ones.
I think this violates some of the basic laws of business: namely if there is an industry with above average profits it will attract competitors and a lowering of price is inevitable. DeBeers was able to control supply, so it was impossible to compete, but now that supply can come from anywhere, it is no longer possible to control.
There’s also moissanites. Moissanites are not diamonds, nor do they claim to be. They are made of silicon carbide and are jewelry-sized synthesized versions of a crystal that naturally only occurs in eensy weensy micro crystals (and are found at meteor impact sites).
A moissanite is notably cheaper than a diamond, real or simulated. They are much more like a diamond than other simulants in hardness and brilliance.
Another popular simulant is a white (colorless) sapphire> For my money, they aren’t as sparkly and are more expensive.
But don’t ask me. People think I have a diamond, emerald, platinum ring, but it’s moissanite, tsavorite, palladium. 
This has been true of the three synthetic diamonds I have examined. I am no real expert, but with a 10x jeweler’s loup the yellowing is pretty marked.
I have looked at my brilliant-cut diamonds and at my CZs, and it looks like the same cut. It may very well be, though, that the diamonds were cut with precise calculations based on those individual stones, while the CZs were just formed that way so they’d look like diamonds.
FWIW the CZs are much sparklier. Too bad they’re in a cheap 10k gold setting that may very well turn my ears green.
They are really?
I am not a diamond or jewerly person by any stretch, but I was always a bit bemused about CZ and peoples reaction. Yeah diamonds are “real” and expensive as shit, and supposedly sparklier. But unless you got some serious bling, your fancy diamond is going to be damn small. With CZ you can get some niced sized babies at an affordable price. A big not so sparkly rock looks tons better than a barely visible super sparkly rock IMO.
They introduce a gas in the process specifically to add color. Man-made diamonds are as naturally clear as any mined diamond. Legally, they could sell perfectly clear man-made diamonds, but the evil bastards at de Beers would sue them into bankruptcy if they tried.
So if a man dams a creek it’s artificial/synthetic/fake? What is it if a beaver dams a creek?
There was an airing of How It’s Made (Discovery Channel) last night (Wednesday May 20) that showed Apollo’s process.
Are you sure about that? I was under the impression that the colored synthetic diamonds are colored because of limitations in the manufacturing process.
Well, if a man-made structure dams a river, the lake behind it is sometimes called an artificial lake.
My rule of thumb would be that a man-made copy of something that exists in nature is called artificial.
Concerning the discussion in this thread, I personally would reserve “fake” to describe objects that look like diamonds but are not diamonds, e.g. cubic zirconium or moissanite. It would seem to me that the objects that are chemically identical to a diamond formed “naturally” (e.g. the stones made by Apollo Diamonds) would be called artificial or synthetic diamonds, but not fake diamonds. I am unaware of any current usage of the term “fake diamonds” for “artificial diamonds” but I am neither a diamond expert nor a language expert.