As the name implies synthetic diamonds look like real diamonds but do not have the same properties as real diamonds. The ability to determine the differences between chemical compusosition, hardness, weight, and some of the light handling characteristics of real diamonds and synthetic diamonds with the naked eye is extremely difficult. Man-made diamonds are not considered synthetic diamonds because they do have the same properties as real or mined diamonds.

Cut Glass was probably the first material used to simulate a diamond. It is readily available, easy to cut and polish and when seen from a distance, looks good. With all of the information available to today's consumer trying to pass cut glass off as a diamond rarely works. Cut glass is still seen in costume jewelry and in the movies today because of its extremely low cost. The use of cut glass has widely been replaced by the most popular diamond alternative, cubic zirconium.

Since 1976 cubic zirconium has been the most widely used material for synthetic diamonds. Its low cost, durability and light handling characteristics have made it extremely attractive in producing low cost jewelry. Cubic zirconium light handling characteristics is so close to that of a diamond that only a trained eye can tell the difference between the two. The annual global production had reached 50 million carats by 1980. Cubic zirconium will weigh about 1.7 times more that a diamond. The hardness rating of cubic zirconium is between 8.5 and 9 whereas diamonds have a hardness rating of 10.

Moissanite or silicon carbide was named after Henri Moissan after he discovered the new mineral in fragments of a meteor found near Diablo Canyon in Arizona 1893. Henri Moissan is also credited as the first person to have created a man-made diamond in a libratory in 1892. Moissanite is a naturally occurring mineral that is slightly softer than diamonds with a hardness rating of 9.25 but has almost all of the other properties of a mined diamond. Charles and Colvard introduced gem-quality moissanite jewelry in 1998. The thermal conductivity test use to distinguish diamond from other artificial stones was rendered useless because moissanite has almost the same thermal conductivity as a diamond. It requires highly specialized equipment to determine if a gemstone is moissanite or a diamond.

With the high quality of synthetic diamond on the market the only way you can be sure that you have a genuine diamond is to have it certified and if you are purchasing a new diamond insist on a certification before purchasing. It will tell you the stone's carat weight, its color and clarity, and its flaws. If the seller is unwilling to supply a certification with the diamond then he may not be telling the truth and you should find someone who will. After all when you want to sell the diamond the new owner will want a certification from you. Here are a few suggestions for testing to see if you are looking at a genuine diamond or a synthetic before you invest in a more conclusive test.

Using your diamond to cut glass to prove that it is hard enough to do so may prove to yourself that it is a diamond but that type of abuse can damage any stone. You could ruin a perfectly pretty piece of jewelry. Another frequently used to test diamonds is called the light test. Shine a black light through the gemstone in question. If a blue light shines though it the diamond could be real.

Careful clean any oil and dirt from the surface of the diamond and then gently blow upon the surface of the stone and if your breath shows for a few seconds after, you have a fake. Genuine diamonds clear up breath almost immediately.