The first method is to check the diamond with the help of diamond tester as it will help you to differentiate between real diamond and best fake diamond. It is an electronic tester that can check all the diamonds except the moissanite stone for which the diamond tester is not reliable. The best fake diamond is the cubic zirconia and the weight of this diamond is around 50% more than a real diamond of the same size and shape. This weighing test also can find out the difference between fake vs. real diamond.
Another method for checking the best fake diamond is the transparency test in which the diamond is placed up side down on the news paper and if the written matter from the newspaper is legible then be sure that the diamond is not the real one and it can be a best fake diamond. One of the disadvantages of this method is that some of the stones may appear to be a real diamond due its fine cutting. In this case, one needs to be sure about the cutting methods of the stones. This method is very common and enables you to find the real diamond from the best fake diamond.
The third method that helps you to differentiate between fake vs. real diamond is the fog test. Hold the stone or the diamond and blow some air from your mouth on to the stone, if the fog appears on the stone and stays there for next few seconds then it shows that the stone is a best fake diamond because in case of a real diamond, the heat disappears instantly. The oily layers and dirt on the stone might create some problems to differentiate fake vs. real diamond. Thus, before carrying out a test for best fake diamond, clean its surface properly.
The ultra violet test is another method that will enable you to find out the real diamond from the best fake diamond. The real diamond projects blue color light if put under the ultra violet light or the black color. There are two options, if the blue light does not appear, it can be best fake diamond or can be a high quality diamond.
All of the above tests can satisfy all the test conditions to differentiate between a best fake diamond and the real diamond.