The 8 Best Diamond Testers for 2023

By Grit Daily Staff Grit Daily Staff has been verified by Muck Rack's editorial team
Published on February 17, 2023

It makes sense to want only the best when you spend your hard-earned money on luxury items. For diamonds, this is especially true. 

If you splurge on what you believe is the most precious stone of them all, the last thing you want is to find out that it is actually moissanite (a diamond-like simulant made of silicon carbide). It is also possible to have inherited jewelry, made a lucky find, or received a gift — and you are unsure of its value.

​​Typically, jewelers have these handy diamond detectors as compact electronic devices. It’s important to confirm the genuineness of diamonds using a jeweler diamond tester. These are portable, handheld devices designed to be carried around in your pocket like a pen.

You will often place a tiny needle-shaped tip on the stone in these devices. The clarity of the stone will be further clarified by a unique sound or visual cue.

Almost all testers operate based on the principles of thermal conductivity. The properties of heat conduction in various materials differ, and diamonds have unique heat conduction properties. In addition to thermal testing, some high-accuracy testers also rely on electrical conductivity.


If you’re in a hurry, here are our top picks for the best Diamond Testers of 2023


Types of Diamond Testers

Diamond testers can be split into two types, but they both operate similarly.

Heat Diamond Testers

To determine the quality of a diamond, testers use heat to create thermal conductivity between the tip and the stone. Based on this data, the tester calculates the quality of the reading based on the speed at which heat passes through the diamond. Moissanite, a gemstone but not a diamond, cannot be detected using a heat tester.

Electric Diamond Testers

If you want the best and most reliable diamond tester, look for one that uses electricity. Testers like these perform the same function as heat testers but provide more accurate results. The price tag for these is higher than that of heat testers. Unlike diamond heat testers, they are able to detect moissanite.

Right now, Amazon has a variety of diamond testers to choose from. Our criteria for choosing the right ones are testers that come from a good brand and provide a good value for their price. We also chose testers that are easy to use and provide solid conductivity.


The Best Diamond Testers of 2023

Diamonds can be distinguished from imitation stones using this portable electronic device. This device is used to identify diamonds quickly, accurately, and safely. The diamond tester tool kit is perfect for handling all diamonds and gems, as well as jewelry and precious metal items.

When the lights are on, voice instructions emit audible sounds, allowing you to easily distinguish between masonry and stone. You can carry small portable electronic devices in your wallet or backpack, and they’re easy to use. The result can be obtained by pressing the switch with the tip perpendicular to the test masonry.

PROS
  • Easy to use
  • Works with a lot of different diamonds
CONS
  • Limited usefulness with gemstones

Test diamonds quickly, precisely, and safely with this diamond selector tester. This tester pen is easy to use and easily explainable. For example, there will be no sounds or lights if the crystal is fake, like cubic zirconium (CZ), crystal, or glass.

Built from durable ABS plastic, this 60X mini magnifier has two bright LED lights and a UV-detecting light. Light from LEDs can improve visibility and can be used in dark environments, while UV lights can be used to spot fake currency notes. The device is equipped with a 9V lithium battery that can be recharged by USB and can be used 1000 times.

PROS
  • Durable
  • Easy to use
  • Intuitive design
CONS
  • Some have had issues with the light

This is one of our personal favorite testers. It is a more sophisticated and precise diamond tester as it identifies whether a diamond is real or fake quickly. This diamond tester and magnifier come with convenient carrying cases.

Designed to speed up, confirm, and ensure diamond quality, it uses non-destructive testing and is precise and fast. There will be at least nine LED lights on the pen, including a green indicator if the stone is a real diamond.

PROS
  • Easy to use
  • Fast results 
  • Portable design
CONS
  • There have been reports of defective products

Here is a combo that is totally worth your buck! With LED lights and an audio indication, the Molo Diamond Tester Pen is a great tool. During a test, the LEDs will light up when the diamond detector detects that the stone does indeed pass the tests. The Diamond Tester Pen will make a beep sound as well as show a row of fully lighted LEDs when it has completed all of its tests.

In addition to the Molo Diamond Tester Pen, there is a slide-out magnifying glass. Moreover, they both come with their own carrying case. If you’re going to a garage sale, flea market, swap meet, etc., the Diamond Tester Pen and 60X LED Lighted Loupe combo is a must-have tool kit.

PROS
  • Provides fast results
  • Comes with a fantastic magnifying tool
CONS
  • Not the most durable tester

This particular tester may be a little more pricey than the others, but the value is miraculous. With its smooth ergonomic shape, the TESTEROSSA easily fits into your hand. The LED stone illumination further increases ease of use.

TESTEROSSA is the best in its class thanks to its intuitive finger grip pads and fast warm-up time! This new enhanced metal identifies, detects, and separates diamonds from CZs, moissanite, and white sapphires.

PROS
  • Very easy to use 
  • Uses colors for a visual experience
  • Great design
CONS
  • Very expensive compared to some other pens

Designed to perform diamond testing quickly, accurately, and safely, this portable electronic device is used to distinguish real diamonds from imitation stones. This tester is portable and equipped with a carrying case. One can use it very easily, as false diamonds won’t display and won’t make a sound.

Meanwhile, it will have a light-up indicator if it is a real diamond. Due to the high-quality ball bearings, the rope won’t twist, tangle, or bend like other fitness ropes, so you can perfectly skip the rope. The tester comes with a small tray for holding loose stones as well as a leather bag.

PROS
  • Smooth and tangle-free
  • Extremely fast
CONS
  • Not a very durable build

Using the Rs Mizar Diamondnite dual diamond tester, you can test non-diamond, synthetic Moissanite, and real diamonds at one touch. There is only an eight-second warm-up time between tests and a one-second recovery time! Portable and powered by a 9-volt battery (included), this tool is perfect for traveling.

The three-minute shutoff feature saves battery life. It also comes with an easy-to-read, gray shell that is shock-resistant.

PROS
  • Warms up quickly
  • High-quality tester
  • Has a 2-year warranty
CONS
  • Expensive
  • Very simple design

This device is designed to help you easily identify diamonds and moissanite from fakes, as it is capable of identifying gemstones smaller than 2 mm. No adjustments are required in the LED bar graph via volume control to match stones of differing sizes, as in other diamond testers. This tester has a metal detector that signals if the metal setting is touched instead of the stone.

In the absence of this feature, other testers can indicate a real diamond even if the diamond is fake when you unknowingly touch the setting. The rubber paint finish on this device gives it a non-slip, safe, and comfortable feel. Additionally, it is equipped with an elastic tip probe for testing and identifying stones of small sizes. The compact design makes it easy to carry when you need it where you need it. In addition, the probe can be used continuously for up to 2 hours and is quick to warm up in 25 seconds.

PROS
  • High accuracy
  • Great design
  • Easy to use
CONS
  • Limited reviews
  • Complaints about quality
  • Pricey

Other Products You May Need

We hope you enjoy these products! But keep in mind, Grit Daily might take a small commission on the items recommended here—but that doesn’t mean we don’t believe in them. We only recommend products that we would buy or use ourselves, so don’t be wary of our suggestions.

By Grit Daily Staff Grit Daily Staff has been verified by Muck Rack's editorial team

Journalist verified by Muck Rack verified

Grit Daily News is the premier startup news hub. It is the top news source on Millennial and Gen Z startups — from fashion, tech, influencers, entrepreneurship, and funding. Based in New York, our team is global and brings with it over 400 years of combined reporting experience.

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