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The Best Gem Tester of 2021

  Updated on 19 October, 2021

Generated From 25K+ Reviews!
SaleBestseller No. 1
Presidium Instruments Gem Tester II (PGT II) with Assisted...
  • INCLUDED ASSISTED THERMAL CALIBRATION | Now easily self calibrate your device to your...
  • INDUSTRIES MOST TRUSTED | Gemstone tester redesigned to be more compact, sturdy and...
  • THINNEST RETRACTABLE PROBE TIP I PGT II features the industry’s thinnest retractable...
  • VERSATILE AND RELIABLE | Consistent and reliable results every time. Identifies...
Bestseller No. 2
Presidium Instruments Gem Tester II (PGT II) Now with...
  • NOTE: The calibration may be affected during shipping. If you have issues, reach out to...
  • INDUSTRIES MOST TRUSTED gemstone tester redesigned to be more compact, sturdy and...
  • THINNEST RETRACTABLE PROBE TIP: PGT II features the industry’s thinnest retractable...
  • VERSATILE AND RELIABLE: Consistent and reliable results every time. Identifies...
Bestseller No. 4
Presidium Instruments Gem Indicator (PGI) Handheld Tester...
  • INDUSTRIES MOST TRUSTED | The only handheld tester specifically for colored gemstones;...
  • THINNEST RETRACTABLE PROBE TIP | Retractable thermoelectric probe tip that ensures...
  • VERSATILE AND RELIABLE | Color input function to further separate gemstones for more...
  • EASY TO READ | Results are on a clear digital LED screen; Tests an extended range of 31...
Bestseller No. 5
Presidium Duo Tester PDT Diamond Gemstone Tester
  • Retractable thermoelectric probe tip that ensures constant pressure between probe and...
  • Industrys thinnest probe tip (0.6mm) for testing gemstones as small as 0.02ct
  • Large easy to read analog dial with 15 colored gemstones
  • Consistent and reliable results every time

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Buyer's Guide: Gem Tester

Gem Testers And Their Types

What is a gem tester and what does it do? How can you tell if your loose rubies, emeralds, topaz's, or whatever stone it is that you have is worth buying? How can you know if it is a good quality stone? It is a device which allows you to test stones in a laboratory setting. The device uses a quartz crystal as a source of electricity. This electrical charge passes through a series of electrodes which are connected to a voltmeter.

A gem tester, also called a diamond tester or a diamond analyzer, removes all the guesswork from choosing gems. Holding the gem tester to the stone or area you wish to test, let the tip of your thermometer probe touch the surface of the stone or area. The screen should now display the results, which should be in meters/inches/centimeters. If the value is wrong, change the settings to reflectivity meter units.

There are several types of gem testers, e.g. diamond moisture testers, Moissanite moisture testers, Thermal conductivity testers, etc. Below are some things you need to know about these different types of lab equipment:

There are a few different kinds of quartz crystal stones, and each one has its own particular characteristic of translucency, clarity, hardness/precitability, etc. This means that it is impossible to use a single diamond stone, or a series of them, in thermal testers. The most common laboratory equipment used to test stones is a thermal conductivity meter. The benefit of using this is that you can use the same type of gem tester for all of your gem-testing needs.

Diamonds are tested by using a diamond thermoelectric probe, which measures the amount of heat released from the surface of the stone. Because diamonds are translucent, a reflected infrared light will not show up on their surface, so a reading of zero will indicate that a gemstone has been completely "cooled". A more accurate reading would be either "locked" or "open", where the crystal serves as a conductor. In a gemstone thermoelectric probe, the gem tester is held at a certain temperature for a predetermined period of time. If the temperature of the probe's tip reaches the maximum threshold (the point where the material becomes conductive), then the stone is considered "cooled".

Another kind of gem tester is the electronic gem tester. When a person looks at a piece of jewelry, he does so with his eyes, not with his hands. Therefore, a purely electronic reading is not possible. The electronic gem tester relies on the conduction process between the material to be tested and the energy vibrations that are associated with it. If the two materials have a similar conduction process, then the value of the result is an estimate of the hardness or softness of the material.

It is important to note that these three types of gem tester do not mean that they are the best. Each has its own strengths and weaknesses. For instance, diamond testers that rely exclusively on infrared technology may not be as sensitive as one that uses a combination of both techniques. Many modern diamond testers are able to obtain more accurate results by using various types of technologies, including electrical conductivity testing and the use of ultra-sound. However, if one is really looking for the best, it is recommended to invest in one that is specifically manufactured for detecting extremely soft metals such as titanium and stainless steel.

Most of these gem testers today can be purchased from reputable jewelers. However, some buyers choose to purchase used models instead. Since these stones are extremely valuable, you should only consider purchasing from reputable jewelers. Before making the purchase, it is wise to get in touch with a reliable jeweler who can help you in identifying genuine gems and helping you make the right purchase.