When someone walks into your shop with a diamond ring or necklace he or she is looking to appraise, you will first want to ensure that the diamond is the real deal. There are a variety of ways to check the authenticity of a diamond, many of which can be done without any major equipment. Below are four ways you can check to see if a diamond is real or fake before entering it into TheLoupe®.

1. If the stone can be removed, turn it upside down on a printed piece of paper, such as a book or any document lying about. If you can read through the stone to see the text, then the diamond is most likely fake.

2. Diamonds are fantastic heat conductors, and you can utilize your breath to tell if one is real or fake. When you breathe on a real diamond, the fog should disappear immediately. However, if it lingers for a few seconds, you are most likely looking at an imposter.

3. Jewelers can also use a thermal conductivity probe to detect the rate at which the stone disperses heat. This test also works on most gemstones.

4. You can also use a jeweler’s loupe or microscope to determine a diamond’s authenticity. Using your preferred magnification method, look at the stone through one of the bezels on the crown. If you see doubling, it is most likely synthetic moissanite.