There is a massive disparity in price amongst diamonds. Clarity, size, cut, and rarity are all significant factors. But a diamond’s authenticity is of utmost importance as well. Money can be left on the table if diamonds are undervalued when they’re sold. Likewise, you don’t want to overpay for diamonds that aren’t real. So, determining a diamond’s status is crucial.

One method is to place the stone in water. It’s said that a real diamond will sink, whereas a fake will float. Granted, this is a moot point for any mounted diamond. And plenty of fakes will also sink like, well… a rock.

Considering different stones conduct heat differently, you can also try your own heat test. Hold a diamond up very close to your face and breath on it so as to fog up the surface. If the condensation from your breath clears after one or two seconds, it’s said to be an authentic diamond. If it stays fogged any longer than that, its thermal conductivity implies a fake. While it’s a good idea in theory, it would be ill-advised to stake such a large investment as a diamond on such an unpredictable test.

Another lesser-known option is to use a black light. Eliminating all other light sources and holding a diamond up to a black light should reveal a blue aura. A green, gray, or yellow glow implies a diamond’s inauthenticity. A fun test to be sure, but not all diamonds radiate a blue glow under a blacklight, so this test is far from foolproof.

While there are many ways to go about testing diamonds, not all methods are created equal. At The Jewelers Toy Store, powered by Rosenthal Jewelers Supply, we offer the best diamond assessment options.

A diamond tester pen is a handheld electronic device. They are small enough to fit in your pocket, making them extremely convenient. Models such as the Presidium Diamondmate C Rechargeable Diamond Tester and the Diamondmate-A Tester work by generating a small amount of heat through the diamond in question. Different materials conduct heat and electricity differently. So, a diamond tester can measure this and use the information to determine if a stone is glass, cubic zirconium, or a genuine diamond.

A diamond tester is one of the most reliable means of assessing authenticity. The only drawback is that thermal diamond testers can give a false positive for a diamond if a stone is in fact moissanite. They do conduct heat in an extremely similar way. Moissanite is not a challenge for diamond testers that rely on electric conductivity, as the two stones conduct electricity in different enough ways.

The best diamond testers use both thermal and electrical conductivity to scan diamonds. Models such as Presidium Diamond Tester, the Asource Diamond Moissonite Dual Tester, and the Gemlogis Lapis Rechargeable Multi Tester are some that use both heat and electricity, and deliver highly accurate results.

Some machines also let you go beyond diamond detection. The Presidium Gem Tester II (PGT II) can sense the presence of up to 16 colored common gemstones. This device is best for sussing out which gemstone you have on hand in situations where the authenticity of the stone is already known, as its thermal capabilities can’t always distinguish real gemstones from synthetics. It’s also great for its large display screen, while still being small and portable. This product also qualifies for free shipping.

When needing to determine between simulant gemstones, the Gemlogis Bleu Rechargeable Colored Stone Gem Stones Testing Machine is an excellent choice. This model can identify as many as 30 different color gemstones including diamonds and moissanite. Also available to ship to you for free, the Gemologis Bleu is easy to use with its touch LCD screen and can be paired to Belize and Mantis via Bluetooth connection.

Speaking of Belize, the Gemlogis Belize Diamond, Moissanite, Simulant Tester is topnotch for differentiating authentic diamonds from simulants. The device is compact and works with both loose and mounted stones. This item is also available to ship to your doorstep for free.

Whatever model is right for you, all our products come with fast shipping. Don’t get scammed by convincing knockoffs. Invest in proper diamond testing equipment and save time and money for your operation for many years to come. Rely on The Jewelers Toy Store to provide you with the best diamond tester and gold tester options on the market.