Many people ask how to differentiate a real diamond from a fake diamond. There are many simple ways to identify that.
01. Compare the weights
One of the easiest ways is to weigh the stone. For this method, you should have a diamond scale but many people do not have diamond scales with them. Howsoever, as for an example, if you compare the weights of the stones as in the below picture, i.e. diamond vs. cubic zirconia (CZ), although the sizes are the same, the weights are different. 
Here, the diamond weight is 1 carat whereas, the CZ has 0.8 carat weight. In other words, 1 ct CZ is bigger than 1 ct diamond.
Obviously there is a big discrepancy in weight and thus, it is like a surefire way to identify a real diamond. Usually, diamonds heavier than moissanite and CZ.
You can easily access through online and look up charts for diamond size and weight equivalents and it will tell you, for example, a 6.5 mm diamond should be approximately one carat. And 8 mm should be a 2 carat etc. There are charts with different shapes. Even though this is the easiest way, if you don’t have a diamond scale this method won’t work for you.
02. Identify Diamonds With a jewelry Loop
Take a jewelry loop like above and observe the stone more closely. Then you will be able to find that the light scattering patterns of the diamond and they are extremely sharp very crisp on cubic zirconia or moissanite or luster material they’ll be more rounded. You can see it even in the above picture as well if you have a close look.
03. Breaths on Diamond
Breathe on the diamond and fog it up and observe whether it lasts about one-two seconds. With cubic zirconia, you’ll see it’s gonna last five to eight seconds. Owing to the diamond’s ability to dissipate heat, it disappears within a few seconds. However, as the other materials don’t have that same ability, it takes longer to dissipate the breath. Hence, persistence more than one-two seconds is an indication of a fake diamond.
04. Read through the stone
The other method is, take a diamond and put over some written book or a newspaper and see whether you can read it or not. With a real diamond, you won’t be able to see through it properly, it is ore like a scattered appearance as shown in the picture.
05. What is the diamond mount look like
The last indication is to look at the mounting. If the stone features a high-end luxury looking mount with engraving logs , it will be a good sing of a real diamond. But remember it can be used expensive settings to some large moissanite and CZ as well. Albeit, if it’s with an elegant looking, expensive mounting with lot of little diamonds, it could be an indication of real but this is not a surefire way. SO do not jump into conclusion with this method.
Hope this guide would help you to identify and differentiate fake diamonds from real ones.
