Diamond Tester

How Much does a Diamond Tester Cost?

Our biggest worry as diamond enthusiasts is ensuring we’re buying a genuine stone. And while many jewelry stores offer proof that their gems are authentic, it’s not always the case when you’re trading with individuals. You may also wish to personally analyze your stone’s quality or run a jewelry store and must ensure that every diamond is the real deal. For these and many reasons, numerous tools are employed to check a diamond’s originality, including diamond testers.

But with these gadgets come a hiccup which is the price. Once you hit the online stores, you’ll be overwhelmed by the expansive array of prices for which different diamond testers are offered. This can get confusing, especially when you’re unsure what to look for, thus unable to determine how the prices are set. But here, we’ll help you understand how a diamond tester’s price is determined and explore the numerous sections that explain why this tool has such significance in the gem industry.

What Is A Diamond Tester?

Before we determine how much it costs to buy a diamond tester, we must first understand it. A diamond tester is a portable tool that helps confirm the authenticity of diamond crystals by measuring their thermal and electrical conductivity. Diamonds have unique measurements for these factors, and the tester is designed to analyze these properties and confirm if the stone is real or fake.

Each tester is built to a portable size that can fit in your pocket and come with a small needle tip that serves as the point of contact between the device and the gem. Colorful light indicators are featured on the body, and a measurement scale highlights what each color range represents. And when the needle tip touches the stone, a light blinks on the gadget, and you can tell from the scale whether it means the stone is a real diamond or not.

Diamond testers operate on a principle based on the fact that gemstones have varying chemical structures and so can’t conduct heat or electricity the same way. And it’s the difference in these chemical structures that allows the diamond tester to indicate what kind of stone you’re handling. Jewelers and gemological agencies have used these devices for decades, making them one of the essential tools for confirming a gem’s authenticity. But today, thousands of device exists, and each with its price based on design, quality, size, brand, type, and range of use.

Diamond Tester, Diamond Detector, Diamond Tester Pen, Diamond Tester Professional, Diamond Detector, gem Tester, Diamond Tester Pen High Accuracy Professional Jeweler(Black Diamond Testers)

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  • EASY AND QUICK TO USE Our diamond detector can rapidly determine whether diamonds, jade, agate, and crystal are genuine. The indicator light and sound will both be more than or equal to 9 if it is a genuine diamond.
  • Our High Accuracy Professional Jeweler, which is in its second generation, has a reasonable design and is very easy to use. Before using, all that is necessary is to flick the switch and install the battery. (void of batteries)
  • Simply open our diamond gem tester and place the Diamond Detector’s tip perpendicular to the gemstone to quickly distinguish between them (90 degrees). You’ll be able to rapidly determine whether the item is real or phoney in only a few seconds.
  • Diamond, jade, crystal, and agate may all be tested with the high accuracy professional jeweller diamond tester pen. The validity of the tested objects can be readily and rapidly verified using the diamond checker tool.
  • ‘SERVICE’ If you have any queries about the use, don’t hesitate to get in touch with us. We’ll get back to you within a day. One Diamond Tester, one User Manual, and one Test Platform are included in the package. This item runs on a 9v battery (battery not included)

Presidium Instruments Gem Tester II (PGT II) with Assisted Thermal Calibration (ATC) for Identifying Diamonds/Moissanites and Common Colored Gemstones

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Types Of Diamond Testers

Diamond testers mostly come in two types, and each is an advancement of the technology surrounding its need and creation. The type also determines how much the tool is sold since gadgets with more advanced technology will offer the best results.

Heat Conductivity Diamond Testers

The heat diamond tester is designed to confirm the stone’s authenticity by measuring its rate of thermal absorption. The chemical structure of diamonds allows heat to pass through the stone at a specific rate, and all true diamonds offer the same measurement for this factor. A heat diamond tester reads the speed at which this property is shown and indicates it on the reader. These testers are the most commonly found, as the technology is based on a simple principle, and the parts are easy to assemble.

Electrical Conductivity Diamond Tester

An electrical conductivity diamond tester works under the same principle as its heat conductivity counterpart but also reads the stone’s electrical conductivity. As heat dissipation is unique in all diamonds, so is how electrical charges pass through the stone. These testers read the rate of such movement and display the measurement on the indicator. Electrical conductivity diamond testers are considered more accurate than their older counterparts, so they cost more and are mostly used by experts.

Diamond Multi-Tester

Though most diamond testers help read a stone’s authenticity, they flop on one area. For instance, heat conductivity testers may not offer a more accurate result due to some gems’ heat absorption sharing a close semblance to the diamond’s. And while electrical conductivity testers will point out most fakes, they may fail when dealing with stones closely similar to real diamonds, like moissanite.

So, to tackle this problem, the technology of heat and electrical conductivity was merged to create a multi-tester. These types are extremely accurate and produced specifically for professional uses. Multi-testers will measure the diamond’s heat absorption rate and electrical conductivity without flaw. This way, you get a better result and won’t have copies or simulants passing as real diamonds due to inaccurate testing.

Why Are Diamond Testers Needed?

Like many other tools, diamond testers are needed to differentiate a real stone from a simulant or imitation diamond. With the huge demand for valuable stones came a desire to satisfy sales and the invention of imitation diamonds. An imitation diamond is a stone that looks and sparkles like a real diamond but is truly a crystal of different chemical composition. Crystals like cubic zirconia and moissanite were sought to give a lower-priced offer to those who wish to own a diamond but can’t afford to buy a real one.

However, diamond simulants have become quite rampant on the market, and some shifty people may be tempted to offer them as the real deal if you’re not cautious. Jewelers own tools like the diamond tester to check if the presented stone is a real diamond. Some individuals also prefer to test for a stone personally, so they seek places to buy gadgets for such a need as the diamond tester. Also, you may be one of those who hunt for raw gems at mines and riverbanks and will need such a tool to confirm if the gems you pick are real diamonds.

Are Diamond Testers Accurate?

The answer to this commonly-asked question rests on the type of diamond tester you’re using. While these tools are generally reliable, their advancement in technology makes some better than others. For instance, thermal conductivity diamond testers will offer an accurate result when used on a real diamond. But you won’t get a solid result when testing moissanite with it.

However, electrical conductivity diamond testers are more accurate, as they’re designed to read the slight difference in this property between real diamonds and similar gems like moissanite. But the most accurate types of diamond testers will be the multi-testers, which combine both the thermal and electrical conductivity reading capacity of both tools. Today, multi-testers are the most used gadgets in professional jewelry stores, and they come with extra features that promote utmost reading accuracy.

Using Testers On Lab-Grown Diamonds

Lab-grown or synthetic diamonds are diamonds created in a controlled environment created by man. These stones were exposed to similar environmental conditions that created natural diamonds in the wild millions of years ago but using artificial equipment and facilities. Lab-grown diamonds carry identical chemical, physical, and gemological properties as natural diamonds and thus test positive on any diamond tester.

However, a diamond tester may not be the right tool if you seek to know whether a stone is natural or manufactured. All synthetic diamonds are real diamonds, and some command a hefty price on the market. But other testing methods are needed for those who only seek natural diamonds. These include processes like detecting strain patterns, color zoning, fluorescence, inclusions, and numerous others.

These methods work when testing for real diamonds because the formation process for lab-made stones leaves tells. And these tells are quite different from those found on natural diamonds, making them easy to identify when observed. Of course, you need expert skill or a pre-knowledge of the process of manufacturing diamonds to note the difference. And in many cases, you can even tell which method was used to produce the cultured diamond.

General Price For Diamond Testers

Diamond testers come in a different range of sizes, and as such, their prices aren’t the same. But the cost of each gadget depends on the brand, quality, and how it operates. For instance, the average price for most diamond testers is $15.00, but this applies mostly to thermal conductivity tools. Electrical conductivity tools can range from $50.00 to $200 depending on the brand and reputation.

Multi-testers, however, command the highest price, with some reaching as high as $350! And as mentioned before, these types are best for professional applications. But if you’re testing small amounts of stones, such a price may be over your head and unnecessary. Your final pick comes down to your requirements, how often you test diamonds, and finally, your budget.

Tips For Choosing The Best Diamond Testers

Deciding on the price range for your proposed diamond tester is easy, but you need to be certain about your choice. As the prices vary, so do their functionality and accuracy. You want to pay for accuracy and quality when choosing a diamond tester. And while a lower-priced tool may seem appealing, you may lose out on perfectly detecting a real stone from a fake one.

So, when choosing a diamond tester, follow these tips for the best results;

  • Choose tools that operate on electrical conductivity. These types offer a more accurate result, and though they are pricey, they won’t be as costly as muti-testers.
  • Always check the brand’s reputation and warranty of your diamond tester before purchase. You’ll want a gadget whose functionality claim can be easily traced and proven. Plus, you’ll want a quality warranty service for cases where the tool needs checking.
  • If you can spare the extra bucks, consider buying a multi-tester. These types offer the best results and can work on a wide range of stones beyond diamonds.
  • Ensure that your diamond tester can take readings across different room temperature ranges. Remember that a part of its technology deals with thermal conductivity, so you’ll need a tool to adjust as the room temperature affects the stone.
  • Choosing a diamond tester that warms up quicker is your best bet for multiple uses. If you are examining many stones, you’ll want the diamond tester to function with little to zero lag time between the examinations.
  • Choose a diamond tester with a metal detector that tells when the metal touches the prong setting instead of the gem’s surface. The reason is that the metal prong may register on the tester as a diamond, thus giving you an inaccurate result. But such an indicator will help you adjust the metal pin and retake the reading.
  • Consider your power source before picking a diamond tester. While some come with an A.C. cord, which you can plug into an external power source, others offer a replaceable battery function to move the tool around without restriction. So, before choosing your preferred tool, consider your work site.
  • Diamond testers with a retracting tip are a great way to save repair costs. These types come with a spring-loaded tip, so you apply the specifically needed amount of pressure when touching the stone. That way, you won’t have to worry about damaging the tip.
  • A heat conductivity diamond tester is a good option for a budget-friendly price but keep in mind that it won’t differentiate a real stone from moissanite. Thus, if you must buy it, prepare to check the stone with further methods after testing it with the tool.

More Tips On Detecting Real Diamonds

Fortunately, most diamond testers, including thermal conductivity gadgets, can tell if a stone is cubic zirconia or sapphire. But moissanite may escape your eye if you use a thermal conductivity diamond tester alone. Plus, even after using an electrical conductivity tester or multi-tester, it helps to be double sure that your gem is a real diamond. As such, other tips can help be confirmed without a doubt.

  • Check for Double Refraction- Unlike diamonds, moissanite produces a fuzzy double cutlet observed from the side facets under magnification. So, if you’re looking to confirm whether the stone is a diamond or moissanite, this is one easy way to do it. Ensure to look through the crown when checking for this factor and not through the table.
  • Check for Certification Number- All real diamonds carry an inscription- a serial key engraved on the girdle, and are unique to each stone. So, you can check for this key under magnification to confirm. Note that the engraving may be extremely small, so use a powerful loupe to examine the stone. Lab-grown diamonds will start to contain the letters ‘L.G.’ while moissanite will carry no number at all.


Diamond testers are a handy tool for checking the stone’s authenticity, but not all of them are priced equally. We’ve shown you the various price ranges for these gadgets and why they’re offered at such levels. So, now, you should have a full grasp of how diamond testers are offered for sale and be able to decide which quality fits your planned budget. Plus, you’ll be able to get the best value for your buck once you’re certain about how to look for the right gadget.