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How to Identify an Uncut Rough Diamond

Rough uncut diamonds are often confused with similar-looking materials such as cubic zirconia, moissanite and quartz. The easiest way to spot a real uncut rough diamond it to use a battery operated diamond tester. Testers can be purchased for about $90 and up and are very accurate in detecting genuine diamonds. The size of a tester makes it especially useful to prospectors, buyers, jewelers and pawn shop owners.

Things You'll Need

Newspaper
Small mirror
Sandpaper (optional)

Instructions

- 1
  Let your stone sit at room temperature for 10 minutes without handling it.
- 2
  Pick it up and put it close to your mouth. Exhale on the stone to "fog it up."
- 3
  Look at the stone and see how long it takes for the fog to clear. If it is 3 to 5 seconds or less your diamond is possibly real.
- 4
  Place the stone on a newspaper if it is not completely cloudy. Try seeing the print through the stone. If you can read the print or see it clearly, the stone is likely a fake. This test can have mixed results if your stone is very cloudy.
- 5
  Scratch the surface of a small compact mirror. A real diamond should have no trouble scratching your mirror. You can also try rubbing the stone with sandpaper. A real diamond should not be scratched. However, doing scratch tests can ruin otherwise beautiful cubic zirconia jewelry and is not recommended.
- 6
  Take the stone to a jeweler if your tests prove inconclusive. A jeweler is your best and most accurate option and will tell you almost instantly if the stone is real or not. Often you can find a jeweler willing to check out your stone free of charge.

Rocks & Minerals