How to Tell the Difference Between Real & Fake Diamonds With a Loupe

Diamonds are a girl's best friend, but crooked jewelers may not be looking out for your best interests. Use these steps and a jeweler's magnifying loupe to identify real stones from fakes--then get an independent appraisal just to be sure..

Difficulty: Moderate

Instructions

Things You'll Need:

• Jeweler's magnifying loupe
• Precious (or not so precious) stones to examine

1. Look at the stone's reflections through the jeweler's loupe under strong light. Real diamonds reflect shades of gray. Rainbow reflections are one sign of a poor quality diamond or a fake.

2. If the stone is mounted, inspect the gem by looking straight down through a jeweler's loupe. You cannot see the bottom or the mounting beneath a real diamond by looking through it from the top.

3. Stones with a high amount of nicks and surface scratches are probable fakes. Although a diamond is not completely resistant to surface abrasions, multiple nicks and cuts are signs of an imitation.

4. Look for clearly defined facets and clean geometry across the diamond surface. Fakes are cut with less care and may not show the razor-sharp lines of a true diamond facet.

Tips & Warnings

• Get an independent appraisal before you buy. Avoid using the jeweler's in-house expert unless you trust the merchant completely and have an established relationship. Before buying a diamond, ask for a certificate of authenticity from the Gemological Institute of America (GIA), which tests stones, issues a grading report and notes unique, identifying marks on a particular gem which must match the stone you are buying. Remember the Four Cs when buying a diamond--color, cut, carat, and clarity.

References

• Identifying fake diamonds
• Spotting fake stones with a loupe