Updated: 22 Jul 2026

10 Best gem tester refractions of 2026

Updated: 22 Jul 2026

#1

Best Choice

PRESIDIUM Electronic GEM Gemstone Diamond Tester PGT by Presidium

9.9

Presidium

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Main highlights

VERSATILE AND RELIABLE: Consistent and reliable results every time. Identifies diamonds/moissanites and most common colored gemstones, both polished and unpolished.

THINNEST RETRACTABLE PROBE TIP: Presidium Gem Tester II features the industrys thinnest (0.6mm) retractable probe tip ensuring constant pressure between probe and gemstone. For testing colored gemstones as small as 0.02 carats. Coated gemstones can also be generally tested with PGT II

INDUSTRIES MOST TRUSTED gemstone tester redesigned to be more compact, sturdy and portable
#2

Best Value

$ASHATA RHG181 Gem Refractometer, Professional 1.30-1.81 RI Jewelry Refractometer, Gemstone Identification Tool for Single Double Refraction$

ASHATA RHG181 Gem Refractometer, Professional 1.30-1.81 RI Jewelry Refractometer, Gemstone Identification Tool for Single Double Refraction

9.8

ASHATA

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Main highlights

Identify Single & Double Refraction Gemstones: Effortlessly differentiate between singly refractive and doubly refractive stones with this high precision refractometer. Quickly and precisely identify cabochons and faceted gems, helping you classify diamonds, sapphires, quartz, and more. Streamline your gemological analysis for faster, more confident identification results.

High Accuracy with Easy Operation: Featuring a clear, readable scale and a simple sample application process, this RI tester delivers high accuracy with easy operation. Perfect for both professionals and beginners, you can quickly master the testing procedure to obtain clear readings. A reliable gemological tool for any workspace.

Accurately Measure Refractive Index 1.30-1.81: This professional gem refractometer is specially designed to precisely measure the refractive index of a wide range of gemstones and solid materials. Quickly and accurately determine the critical angle to identify unknown specimens, making it an essential tool for gemologists, jewelers, and hobbyists. Provide reliable data for gemstone identification and valuation.
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#3

$Gem Refractometer, Jewelry Refractometer, RHG181 1.30-1.81 Professional Ldentification Gem Refractometer, Gem Portable Refractometer with 3ml Reflective Index Fluid, for$

Gem Refractometer, Jewelry Refractometer, RHG181 1.30-1.81 Professional Ldentification Gem Refractometer, Gem Portable Refractometer with 3ml Reflective Index Fluid, for

9.6

Gugxiom

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Main highlights

MATCHING 30ML REFLECTIVE INDEX FLUID: This diamond tester kit also comes with a matching 30ml reflective index fluid. With this and other products to you can directly identify jewelry, not in another bottle of reflective index liquid, can save a lot of time.

HIGH PRECISION, SMALL SIZE, EASY TO CARRY: Refractometer high precision, easy to operate. Light weight, small size, easy to carry. Since the refractive index varies from stone to stone, it provides an important identification feature. Refractometers are also one of the few instruments that can provide you with information on opaque and transparent .

ABS MATERIAL: This gem tester is made of ABS material. This material is hard and wear-resistant, which can meet the operator's appraisal needs in daily or professional jewelry appraisal, and has a long service life.
#4

$Gem Refractometer, Professional High Accuracy Jewelry Gem Refractometer Quick Identification 1.30 to 1.81 Measuring Range, Jewelry Refractometer for Identifying and Authenticating Polished Gems$

Gem Refractometer, Professional High Accuracy Jewelry Gem Refractometer Quick Identification 1.30 to 1.81 Measuring Range, Jewelry Refractometer for Identifying and Authenticating Polished Gems

9.3

BTER

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Main highlights

【QUICK AND ACCURATE IDENTIFICATION】The gemstone identification gem refractometer can quickly and accurately identify a variety of single and double gemstones, helping to identify diamonds, moissanite, etc. Help you easily identify the advantages and disadvantages of jewelry.

【JEWELRY GEMSTONE IDENTIFICATION TOOL】The primary use of this gem refractometer is to measure the angle at which light is bent or refracted through a stone. Specially designed for measuring the refractive index of gemstones and solid materials.

【CLEAR DISPLAY AND EASY TO READ】With integrated light source and clear visible display, you can use the refractometer gemstone in different environments. The jewelry refractometer is the main tool for gemologists and jewelers to identify gemstones.
#5

$Gem Refractometer, Professional Gemstone Ldentification, Gem Ldentification Tester with Reflective Index Fluid for Jewelry Diamond$

Gem Refractometer, Professional Gemstone Ldentification, Gem Ldentification Tester with Reflective Index Fluid for Jewelry Diamond

9.2

MUNEFE

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Main highlights

REFLECTANCE INDEX FLUID: This refractometer requires the surface of the clear stones to be polished flat for testing, and the kit includes 3ml of Reflective Index Fluid. Uniform and reliable results are obtained every time with a clearly visible display.

EXCELLENT PERFORMANCE: This refractometer is designed to measure the refractive index of gemstones and solid materials, measuring the angle of bending or refraction of light as it passes through a gemstone.

EASY TO USE: The refractor is highly accurate and easy to operate. Light weight, small size, easy to carry. Since the refractive index varies from gemstone to gemstone, it offers the important gemstone identification function, giving you a good feeling of use.
#6

$Xiuganpo Gem Refractometer High Accuracy Lightweight Professional for Jewelry Identification 1.30-1.81 for Gemstone Enthusiasts$

Xiuganpo Gem Refractometer High Accuracy Lightweight Professional for Jewelry Identification 1.30-1.81 for Gemstone Enthusiasts

9.0

Xiuganpo

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Main highlights

[PRECISE GEMSTONE IDENTIFICATION] Quickly and accurately measure the refractive index of gemstones and solid materials.

[HIGH ACCURACY] Ensures precise readings for single and double gems identification.

[COMPACT AND PORTABLE] Lightweight design for easy transport and use on-the-go.
#7

$ZAICOLER RHG181 Gem Refractometer for Jewelry AppraisersGem Collectors,Identifies Jade,Colored GemstonesPrecious Stones,1.30 to 1.81 RI Range,Includes Refraction Oil,Port ABS Design$

ZAICOLER RHG181 Gem Refractometer for Jewelry AppraisersGem Collectors,Identifies Jade,Colored GemstonesPrecious Stones,1.30 to 1.81 RI Range,Includes Refraction Oil,Port ABS Design

8.9

ZAICOLER

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Main highlights

PROFESSIONAL SPECIFICATIONS - Lightweight 870g ABS construction, compact 13*6*3.5cm size, identifies isotropics and anisotropics stones, works with faceted gems over 2mm in diameter for reliable testing results.

ON SITE TESTING CONVENIENCE - Perfect for jewelry store appraisals, gem market transactions, and field collection trips, portable design lets you conduct authentication anywhere without heavy lab equipment.

ACCURATE GEM IDENTIFICATION - Measures refractive index from 1.30 to 1.81 RI, precisely identifies polished precious and semi precious stones, detects single or double refraction properties to verify gem authenticity fast.
#8

$GLOGLOW Diamond Testers ABS Gem Testing Tool 1.30 to 1.81 RI with Flashlight and Refractive Oil for Jewelers Gemology Students Gem Detector Portable Jewelry Refractometer Lightweight$

GLOGLOW Diamond Testers ABS Gem Testing Tool 1.30 to 1.81 RI with Flashlight and Refractive Oil for Jewelers Gemology Students Gem Detector Portable Jewelry Refractometer Lightweight

8.8

GLOGLOW

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Main highlights

【Ready To Use Set】Package includes 1 refractometer, 1 electric torch, 1 English manual, and 3 ml refractive index fluid, providing the basic accessories needed for gemstone testing tasks.

【Portable Refractometer】Built as a lightweight ABS jewelry refractometer, this gem testing tool measures about 13 x 6 x 3.5 cm and is easy to carry for gemology study, shop counters, and field use.

【Accurate Gem Testing】This gem detector is designed to measure refractive index from 1.30 to 1.81 RI, helping identify gemstones and distinguish single and double gems with clear scale reading.
#9

QUMOX Diamond Tester II V2 with 60X LED Loupe – Portable Electronic Gemstone Selector Tool for Diamond, Moissanite & Gem Testing – High Sensitivity Thermal Conductivity Detector with Sound & Light Ind

8.7

QUMOX

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Main highlights

Portable & User-Friendly Design - Compact handheld tester made with durable ABS housing, high-sensitivity alloy probe, and anti-slip body. The lightweight design fits comfortably in your hand and comes with a protective carrying case.

Fast & Non-Destructive Testing - Provides quick results in seconds with no damage to gemstones. Ideal for jewelers, collectors, and appraisers. Simple calibration ensures consistent accuracy for different stone sizes and temperatures.

Accurate Diamond Identification - Detects real diamonds based on thermal conductivity — instantly distinguishes diamonds from moissanite, cubic zirconia, and other simulants. LED and sound alerts ensure precise, easy-to-read results every time.
#10

Diamond Tester Diamond Selector Gemstone Tool Gems Jewelry Test Tool LED Audio High Accuracy Professional Jeweler for Novice and Expert

8.5

Yotsuba

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Main highlights

Operation is simple and accurate.

Emit audible sounds to give an accurate reading.

Diamond indicator will be shown if the stone is a REAL diamond (Green light).

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10 Best gem tester refractions of 2026

PRESIDIUM Electronic GEM Gemstone Diamond Tester PGT by Presidium

9.9

Main highlights

ASHATA RHG181 Gem Refractometer, Professional 1.30-1.81 RI Jewelry Refractometer, Gemstone Identification Tool for Single Double Refraction

9.8

Main highlights

Gem Refractometer, Jewelry Refractometer, RHG181 1.30-1.81 Professional Ldentification Gem Refractometer, Gem Portable Refractometer with 3ml Reflective Index Fluid, for

9.6

Main highlights

Gem Refractometer, Professional High Accuracy Jewelry Gem Refractometer Quick Identification 1.30 to 1.81 Measuring Range, Jewelry Refractometer for Identifying and Authenticating Polished Gems

9.3

Main highlights

Gem Refractometer, Professional Gemstone Ldentification, Gem Ldentification Tester with Reflective Index Fluid for Jewelry Diamond

9.2

Main highlights

Xiuganpo Gem Refractometer High Accuracy Lightweight Professional for Jewelry Identification 1.30-1.81 for Gemstone Enthusiasts

9.0

Main highlights

ZAICOLER RHG181 Gem Refractometer for Jewelry AppraisersGem Collectors,Identifies Jade,Colored GemstonesPrecious Stones,1.30 to 1.81 RI Range,Includes Refraction Oil,Port ABS Design

8.9

Main highlights

GLOGLOW Diamond Testers ABS Gem Testing Tool 1.30 to 1.81 RI with Flashlight and Refractive Oil for Jewelers Gemology Students Gem Detector Portable Jewelry Refractometer Lightweight

8.8

Main highlights

QUMOX Diamond Tester II V2 with 60X LED Loupe – Portable Electronic Gemstone Selector Tool for Diamond, Moissanite & Gem Testing – High Sensitivity Thermal Conductivity Detector with Sound & Light Ind

8.7

Main highlights

Diamond Tester Diamond Selector Gemstone Tool Gems Jewelry Test Tool LED Audio High Accuracy Professional Jeweler for Novice and Expert

8.5

Main highlights

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