Fogging stone
One of the simplest ways to check the authenticity of a diamond lies in the definition of its reaction to moisture. Hold the diamond to your mouth and slowly exhale it. If you notice that the stone fog up for a few seconds, most likely a fake diamond. A genuine diamond has the ability to dissipate heat instantly, so blurred it is almost imperceptible. If you'll see this blurred, it disappears much faster than fake diamonds. In addition, if you repeat this experiment several times, on a real diamond, the result is always the same. Fake stone with each new approach will moisten all the more, it produces condensate.
Metal
If you check the authenticity of a diamond on jewelry, pay attention to the metal into which it is placed. Earrings, rings and other jewelry with a real diamond is likely to be made of gold, silver or other valuable metal. Armed with a magnifying glass and check the product for presence of a mark on the sample. If available, the probability that a diamond is genuine is very high. At the same time, you may find the inscription CZ (cubic Zirconia), which means that the diamond is of synthetic origin.
Natural defects
Real diamonds usually have an ideal composition. Look closely at it with a magnifying glass. If you see specks of extraneous minerals or small color changes, the probability that a real diamond is very high. Synthetic diamonds are grown in the laboratory, they do not have these defects, because are made in a sterile clean. However, the absence or presence of such defects can not be the determining factor. Even real diamonds can be perfectly clean. Be sure to conduct additional research.
Refraction
If you have a fairly large stone, you can determine its authenticity by checking its refraction. Pick up a newspaper and look at it through the diamond. If you will be able to read printed text, or at least see him with the big distortions, to be sure, this is a fake diamond. Genuine diamond very strongly refracts the light, so to see anything specific for him is almost impossible, unless prepared in a special way.
Heating
Real diamond is a very hard material, it is quite difficult to break. Heat the stone using a small fire for 30 to 40 seconds, then quickly dip it in a glass of cold water. If the stone is made of glass or quartz, it is quickly covered with cracks.