How to Test a Loose Diamond on a Stand Holder

Testing a loose diamond on a stand holder will help determine whether the diamond is an authentic stone or a replica. Fake diamonds are sold at auctions, on the Internet, and in untrustworthy jewelry and pawn shops across the nation every day. A reputable jeweler or a jewelry appraiser provides the best comprehensive testing and analysis of a diamond's authenticity and value. An appraiser can weigh the diamond, measure the stone, grade its color and clarity, and provide a retail replacement value. Without relying on a jeweler or an appraiser, testing a loose diamond on a stand holder can provide keen insight into the intrinsic value of the stone. These simple tests are not foolproof, but they can help test a diamond's authenticity.

Things You'll Need

• Magnifying glass or a jeweler's loupe
• Ultraviolet light

Instructions

1. Perform a visual test to check for any markings on the diamond. While the diamond is on a stand holder, use a magnifying glass or a jeweler's loupe to study the center ridge that encircles the diamond. This center ridge of the diamond is referred to as the girdle. A visual test with magnification can be used to search for laser engraved inscriptions that can be placed on the girdle of a diamond to ensure its authenticity. These laser inscriptions are typically serial numbers that protect the diamond owner from theft. If visible numbers are present on the girdle of the diamond, there is a strong chance that the diamond is genuine.

2. Perform a fog test. Bring the mouth close to the stone and breathe on the surface of the diamond while it is resting on a stand holder. A genuine diamond will clear the fog from a breath almost immediately. Within a brief second, the diamond will appear completely clear and translucent. If the diamond remains foggy or cloudy for several seconds, there is a good chance the diamond is a fake.

3. Administer a loupe test while the diamond is on a stand holder. Use a magnifying glass or a jeweler's loupe and look at the diamond from the top to see how well the cuts, also known as the facets, on the diamond come together. To test positive as a real diamond, the facets should be sharp and crisp in their appearance, and not rolled or curved. Study the girdle and see if it is frosty or waxy in appearance. A genuine diamond has a frosty girdle appearance. Look for flaws in the stone like little black specks, tiny cracks, or small white feathers. These tiny flaws are a positive test that the diamond is genuine, since it is difficult to purposely put flaws and inclusions in a fake stone. However, if there are visible rainbow reflections in the stone, it is likely a fake or a low quality diamond.

4. Perform an ultraviolet light test. While the diamond is resting on a stand holder, hold an ultraviolet light, or a black light, under the diamond. If the diamond shows a blue fluorescence, there is a very high probability that the diamond is authentic. However, high quality diamonds often do not show fluorescence under a black light. So, a lack of blue fluorescence doesn't necessarily mean the diamond is counterfeit; on the contrary, it could mean the diamond is high quality. However, the appearance of other colors, like green, yellow, or gray fluorescence, often prove that the diamond is not genuine.

5. Use an electronic diamond tester. Diamond testers check for the true carbon nature of a diamond and beep if the diamond is authentic. While the diamond is situated in a stand holder, run the electronic diamond tester over the surface of the diamond. Hold the tester approximately 1 inch from the stone while testing. If the tester beeps and displays a green light, the diamond is genuine. As a note of caution--when using an electronic diamond tester, moissanite is the only stone that can fool an electronic diamond tester.

Tips & Warnings

• When using a jeweler's loupe, place the eye close to the loupe for the best view. Do not hold the loupe away from the face as if it were a magnifying glass.

• Do not try the old trick of scratching glass with a diamond. Scratching glass can dull the edges of a diamond's facets. This could lead to a significant decrease in the diamond's intrinsic value.

References

• Abazias Diamonds: How to Test a Genuine Diamond
• Diamond Cutters International: Is It the Real Thing?
• National Jewelers Supplies: Diamonds--Real or Fake

Resources

• I Love India: How to Tell if a Diamond is Real