How to Test a Diamond's Authenticity

Even a well-cut diamond will have blemishes, unlike some other gem stones.

A diamond is the hardest substance known to exist and can be up to three billion years old. Because of this, the diamond can have a rough and rocky appearance when the sides are viewed closely, even after it has been cut by the best jeweler. Other gems often have smooth, even waxy-looking surfaces. A few simple methods can help you decide whether your stone is real, fake or another type of gem.

Things You'll Need

• Toothbrush
• Newsprint
• Magnifying glass
• Microscope
• Glass
• Black light

Instructions

1. Clean your diamond with a toothbrush and warm water. Breathe onto the diamond. If the fog disperses before three seconds, it is likely a diamond. Diamonds quickly disperse heat.

2. Put the diamond on newsprint with the pointy side facing up. With a magnifying glass, try to read the letters under the diamond. If you can, the diamond is fake. Real diamonds scatter light.

3. Look at the diamond under a microscope. All of the line junctions should be precise. Any imprecise junctions indicate a fake.

4. Feel the edge of the diamond. If it is rough, it could be real. Fake diamonds often have smooth edges.

5. Scrape your diamond across glass. This is the least effective method because some other hard gems scratch glass. You may also damage your diamond.

6. Hold the stone over a black light. Many diamonds will have a blue color when under the light, though a lack of blue coloring doesn't necessarily mean the gem isn't real.

References

• Diamond Cutters International: Is it the Real Thing?

Resources

• YouTube.com: Diamond Information, Ways to Tell if a Diamond is Fake