The Rarity Debate
If you ask a geologist, he or she will probably tell you that the rarity of diamonds is a hoax. Apparently, mineral deposits such as kimberlite where diamonds form are very prevalent in the earth s crust. Other conditions and geological deposits exist that give scientists (generally) the impression that diamonds are not as rare as fine rubies, fine sapphires or fine emeralds.
There is a widely popular conspiracy theory that the DeBeers company (which controls 70% of the worlds diamonds) is limiting the number of diamonds that enter the market and therefore keeping the price artificially high.
So just in case, if you like the pretty sparkly little treasures, by them for your own enjoyment and not because they are rare.
The majority of diamond mining takes place in impoverished regions of Africa (Botswana, South Africa, Angola). War and poor labor conditions in these areas can mean that our diamonds come to us at the cost of human rights violations. There are diamonds that are certificated as being controlled throughout the supply chain (from mine to jewelry). Examples are the Canadamark and the Forever mark.
Diamond is more resistent to scratching than a CZ, and a CZ is a bit denser than a diamond: it might feel "heavier" in your hand. But truly, gemological equipment is needed to ascertain for certain what the stone is.
The term "moissanite" has been coined to refer to another type of diamond imitation. Like cubic zirconia, the marketing and selling of moissanite is usually a transparent practice. Again diamond is slightly harder than moissonite, but these 2 gem materials are extremely hard to distinguish without gemological testing.
A con artist might try to sell you another material as diamond, such as colorless corundum or leaded glass. If you are about to buy a "diamond" off a guy from the back of his pick-up, or from a market in China (first of all, not good ideas), bring a ruby or sapphire with you and rub it against the "diamond." If it is a real diamond, it will not be scratched (it will scratch your ruby, so choose an inconspicuous spot on the girdle). Also, check for the properties of diamond:
make sure it is highly reflective and flashing rainbow colors.
A man made or "created" diamond would technically be a real diamond in every sense. The difference is that one is made in a labratory and one is made in the earth. There is some uncertainty and debate about whether true man made diamonds exist in the jewelry market, but it seems that it might be the case. Diamonds have been synthesized for many decades but only for industrial purposes: ugly, small diamonds are manufactured for the use of drill and saw making, for example. Popular speculation is that scientists in Russia may have successfully created gem quality diamonds that are impossible to distinguish from natural diamonds. The DeBeers company is actively pursuing testing and claims to have developed a machine that can tell the difference. But it is all very uncertain...