Diamonds are costly treasures. The majority of people in the market for one are looking for a good stone that is still a bargain. These days’ shoppers often look to online auctions, estate sales, and online jewelers. For the most part all these options are honest businesses, but we still might worry about the diamond’s authenticity.

This is a valid question with so many manmade stones now on the market. Most of them look like the real thing. Let’s face it, most of us can’t tell the difference, unless the stone is cut glass or crystals, or some of the colorless gemstones. Those made from cubic zirconium or Moissanite, using the latest technology, are harder to spot as fakes.

Ideally, you should have any diamond checked out by a legitimate jeweler or certified diamond cutter. It’s hard to do that when you’re buying from an online auction site but it’s worth it to find a way. You could lose a lot of money and be dreadfully disappointed if you learn you bought a fake. There are some things to do if you think you’re being shown a cubic zirconium.

One good test is simply to breathe on the gem. If it’s a cubic zirconium, then the fog will stay on it for a while. If it’s truly a diamond, it will clear up right away. Another method is to try writing on it with an ink pen. Ink balls up on a cubic zirconium and makes a line on a diamond. One more thing to try is to turn the stone over and try reading a newspaper through the back. If you can easily make out the print, then you probably are holding an imitation. This wouldn’t be true however, with a real diamond that was cut shallowly.

Another test is to check the weight. A cubic zirconia stone will weigh 55% more on average than a real diamond. If you have a similar size and shape diamond or have a gram or carat scale, the stone’s weight can be compared to help you determine – real or fake. Many real diamonds have fluorescence blue when placed under a black light but 99% of the manmade diamonds do not. Therefore, try holding the stone under the black light, looking for a medium to strong appearance of blue. If you see this, then the stone is real. While this will tell you if the diamond is real, keep in mind that the bluer the color, the lower quality the diamond.

You can also place the stone under a magnifying glass. Look at the facets from the top and see how they are joined. In real diamonds the facets have sharp rather than rolled edges. The girdles should be faceted or frosty, rather than clear looking. If they are too resinous or slippery, you know the stone is not a real diamond. These tips should help you make sure you get your money’s worth when you buy a diamond.