Moissanite is a very affordable alternative to diamonds, one that everyone can afford. The reproduction of moissanite in a laboratory began in 1995. Created moissanite is a lab created stone that is based on the structure of natural moissanite, which is a crystal found in meterorites. Because moissanite occurs so rarely and is so small in nature in order to supply jewelry needs it is grown in labs.
Moissanites are not sold by carat size like diamonds, but are sold by size measured in millimeters. Charles & Colvard who are the sole-source manufacturer of moissanite do not allow jewelers to sell loose stones.
Laboratory created moissanite has a hardness rating of 9.25. The hardness rating of a diamond is 10. It is said that the most important characteristics of a jewel are it's beauty, durability and rarity. Some lab created moissanite stones actually have more brilliance and luster than actual diamonds. These are called optical qualities. Created moissanites are as clear or "eye clean" as SI quality diamonds. Created moissanite is able to withstand heat better than a diamond. At a temperature of 1100 degrees Celsius a diamond will catch fire, burn, and eventually vaporize. A created moissanite stone will remain intact.
The good news about created moissanite is that some jewelers cannot tell the difference between colorless created moissanite and colorless diamonds. However, you want to make sure that what you are purchasing is actually a moissanite and not a much cheaper imitation CZ. There are lab instruments available to jewelers to help them distinguish the difference. Jewelers can use a probe called a moissanite probe or microscope and some know how to distinguish "double refraction" in moissanites.
To make sure that what you purchase is a moissanite and not a cheap imitation make sure you buy from a reputable dealer and get a written verification from this dealer. It is also suggested that you get a written verification of the stone as well as a certified appraisal.