What is a Diamond Tester? 5 Most Popular Diamond Testers

Diamond testers are considered one of the useful supporting tools that help users quickly check the properties of a diamond, thereby providing a basis for evaluating the value and quality of the stone. This is especially important when you are considering high-value jewelry products such as diamond engagement rings, where the quality of the stone plays a crucial role. However, not everyone fully understands how to use a diamond tester correctly and effectively, as well as its limitations. In today's article, Jemmia would like to share important information about diamond testers, so please follow along.

What is a Diamond Tester?

A diamond tester pen is a specialized handheld device used to quickly check if a stone is a diamond or not, based on the characteristic physical properties of diamonds. Thanks to its compact design, the diamond tester pen is convenient to carry and use in various situations such as buying, selling, exchanging, or initial checks at the store.

Most diamond testers on the market today primarily operate based on the principle of measuring thermal conductivity – a prominent characteristic of diamonds compared to imitation materials like glass or CZ stones. Some more advanced testing devices can combine the ability to measure electrical conductivity, helping to distinguish diamonds from Moissanite more accurately.

It should be noted that a diamond tester is only a preliminary testing tool, helping to distinguish diamonds from common fake stones. This device cannot determine natural diamonds or lab-grown diamonds, nor replace in-depth appraisal processes at reputable laboratories such as GIA or IGI.

Nevertheless, with its convenience and non-damaging effect on the stone's surface, the diamond tester remains a powerful assistant for jewelers, jewelry sellers, and anyone who wants extra peace of mind when owning or trading diamonds.

Natural Diamond Tester – Diamond Testing Machine

Functions of a Diamond Tester

Diamond testers have a range of outstanding functions, the most prominent of which is the ability to distinguish between diamonds and imitation gemstones like cubic zirconia (CZ) or other simulants. This is an indispensable supporting tool for jewelers, jewelry stores, and individual consumers in the following situations:

• Distinguishing Natural and Lab-Grown Diamonds: Diamond testers help users distinguish between real diamonds and lab-grown diamonds, which is quite difficult to do with the naked eye.
• Checking Value During Buying and Selling: When conducting diamond-related transactions, testers help buyers and sellers determine the actual value of the stone, ensuring transparency and accuracy.
• Pre-appraisal Before Repair or Warranty: Before a diamond is repaired or undergoes warranty service, jewelers often check the stone's hardness, heat resistance, and pressure resistance using a tester, giving them a detailed understanding of the diamond's structure and durability.

These functions make the diamond tester a useful and reliable device in the jewelry industry.

Functions of a Diamond Tester

Operating Principle

The operating principle of a diamond tester relies on the thermal and electrical conductivity properties of a diamond. Specifically, diamonds have very high thermal conductivity compared to most other gemstones. When the probe tip of the tester touches the surface of the stone, the device measures its thermal conductivity. The result is displayed through lights or sounds, depending on the type of tester.

• If the tester emits a green light: The tested stone is a real diamond.
• If the tester emits a warning sound or a "buzz": This indicates that the tested object may be metal.
• If there is no reaction: This means the tested stone is fake or a simulant like cubic zirconia (CZ).

The fact that testers rely on thermal and electrical conductivity helps to test diamonds without leaving any damage on the stone's surface, ensuring accuracy and safety during use.

Operating Principle

How to Use a Diamond Tester

Using a diamond tester is very simple and easy to perform with the following steps:

1. Turn on the pen's light switch: When the "LAMP ON BATTERY OK" light turns on, the device is ready.
2. Adjust the scale: Based on the weight of the diamond on the parameter table, adjust the scale light accordingly. In Vietnam's climate, experts recommend setting it to level 3 due to the influence of hot and humid weather.
3. Place the probe on the diamond's surface: Perform the test by placing the pen's small probe on the diamond and wait for the result to be displayed.

How to Use a Diamond Tester

TOP 5 Most Popular Diamond Testers with Prices

Gemtrue Jem-II Diamond Tester

The Gemtrue Jem-II is one of the trusted products for diamond testing. The device has a small probe for easy stone testing, with results displayed on the screen and accompanied by audible alerts. Additionally, this device features a UV light to identify other gemstones like jade, sapphire, and pearls. The product price ranges from 1.5 million to 2.5 million VND.

The Presidium Adamas Diamond Tester

The Presidium Adamas is a specialized device that classifies natural diamonds, moissanite, and other synthetic gemstones based on differences in temperature and electrical resistance. With the ability to record over 500 test results and a small probe for detailed testing, the product costs between 10 million and 15 million VND.

Presidium Multi Tester III

This device helps distinguish colorless diamonds from other gemstones like moissanite, sapphire, and spinel. With a probe diameter of only 0.6mm, the Presidium Multi Tester III is suitable for testing small melee diamonds under 0.02ct. The product price is around 5 million VND.

StillCool Diamond Tester

StillCool is a compact testing device that uses thermal conductivity to distinguish diamonds from other gemstones. This device uses rechargeable batteries, saving costs and protecting the environment. The product price ranges around 1 million VND.

GemOro UltraTester 3+ Diamond Tester

The GemOro UltraTester 3+ is a high-end product capable of accurately distinguishing diamonds, moissanite, and sapphires. The device features an LED screen, an illuminated light, and is rechargeable via USB. It also has an automatic shut-off mode to save battery. The product price ranges from 4.5 million to 6 million VND.

We hope that with the information shared in this article, you have found the answer to your question about “What is a Diamond Tester? Its Functions and How to Use It” that you were wondering about at the beginning of the article. Frequently visit the Jemmia Diamond website to update more information about gemstones and jewelry, as well as the latest diamond jewelry trends.

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