How Do Diamond Testers Work and Is a Jewelry Diamond Tester Accurate?

What is a Diamond Tester

Find out what a diamond tester is and if it really detects real authentic diamonds. Let’s examine a few things about diamond testing and take a look at the science behind how they really analyze a diamond.

Diamond testers will tell you if the gem is real by measuring the amount and speed with which heat travels through the stone. Diamond detectors can also use electrical conductivity which measures the amount and speed through which electricity travels through the stone.

Do Diamond Testers Really Work and How?

Portable diamond testers actually do work and have proven to be very handy if you don’t know the authenticity of a diamond. A basic diamond detector uses its heated needle tip made of metal to cause a heat transference once placed on the diamond’s surface (thermal conductivity). You will then get a result that will let you know if the diamond is real or fake.

StillCool Diamond Tester II V2 Selector Gemstone Jewelry Gems Tool with Case (New Diamond Tester)
Heat-based diamond detector/diamond selector

The science behind a diamond tester is that heat or electricity transfers through other elements like glass or a fake diamond like cubic zirconia differently than the way it would pass through that of a real diamond. They are extremely accurate and will save you much time and effort when you are testing diamonds.

Looking for the best diamond testers? We reviewed the top 5 diamond testers here.

What Type of Diamond Tester is Better? Heat or Electric?

If you are thinking of purchasing a diamond tester, what type is the best choice? Of the two different tools, research has shown that electrical conductivity diamond testers are much better than thermal conductivity diamond testers. They are higher in price, but much more accurate. Heat testers are much cheaper but their accuracy is not as high, so may not get as good results.

Presidium Gem Tester II (PGT II) for Identifying DiamondsMoissanites and Up To 16 Common Colored Gemstones
Electricity-based diamond tester

If you will be detecting up to several diamonds a day or you are a professional jeweler, make sure to buy a diamond tester that uses electrical conductivity for high accuracy. Why? Because there is one type of “fake diamond” called moissanite that can only be detected with electricity. Moissanites are actually rare unique crystal gemstones that have their own beauty but are not diamonds.

Presidium Adamas Diamond And Moissanite Tester
Presidium Adamas Diamond And Moissanite Tester

Technology is always advancing and there are so many accurate models on the market that are extremely precise in their testing. If you use an electrical conductivity tester you will be sure to get a correct answer.

Will Diamond Testers work on Ruby or Real Gem Stones?

Yes! A diamond tester will also work on ruby or and other real gemstones. A diamond tester uses the same technology to detect if a gemstone is truly real. Diamond testers not only work on diamonds and rubies but all other types of jewelry and stones. You can test stones like emeralds and sapphires as well to see whether they are real or fakes.

Gemoro Testerossa Diamond, Moissanite & White Sapphire Tester
Gemoro Testerossa Diamond, Moissanite & White Sapphire Tester

Rubies can actually be very difficult to detect from garnets especially if they are darker in color. So diamond testers really come in handy in that situation. Just because a ruby is dark in color doesn’t necessarily mean that it is a fake.

What about Lab-Grown Diamonds?

You might be asking well what about man-made diamonds (Lab Diamonds)? Are they not comprised of the same material as a real diamond? Can diamond testers tell the difference?

No, diamond testers can not detect a Lab-Created diamond because a lab diamond is real and chemically identical. Lab diamonds are comprised of the same chemical makeup as real diamonds. Natural diamonds have very much the same physical elements as lab-created stones. Even to a very well trained jeweler’s eye, these lab-created gems will pass any diamond test and cannot be told apart from diamonds made by the earth.

Final Notes on Detecting Fake Diamonds

There are many methods and ideas out there for how to tell if a diamond is a fake or not. It’s smart not to leave it up to chance though because these procedures or methods are not completely accurate. An electrical conductivity diamond tester will give you an accurate fast result every time and will never let a real diamond or gemstone slip through your fingers again!

Make sure to learn more about spotting fake diamonds:

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Carl Jones

Carl has been involved in the jewelry business since his youth. Growing up in South Africa his parents were jewelers who worked in the industry for decades.

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