Although most people approach professional jewelers to figure it out, there are a few ways, in which you can tell apart a real diamond from a faux gem.
Check the Diamond Ring Setting and its Mount
It is unlikely for a diamond to be set in an extremely inexpensive metal. A stamp within its setting that indicates real platinum or gold is a good sign, whereas a “CZ” stamp is a giveaway that the centerpiece gemstone is a synthetic diamond called Cubic Zirconia.
Use the Fog Test
Put the gemstone in front of your mouth and then breathe on it. In case the diamond stays fogged for even a couple of seconds, then it is likely to be an imitation stone. A real diamond, on the other hand, would disperse hot air instantly and will not easily fog up.
Analyze with a Loupe
A natural diamond typically has small inclusions that can be seen with a magnifying loupe. Look for tiny flecks of minerals or extremely slight changes in color. They are signs that you are holding a real diamond with naturally occurring flaws.