10 Best gem testers of 2025

Explore top picks

Best Choice

1

Presidium
Presidium Instruments Gem Indicator (PGI) Handheld Tester for Identifying Diamonds and Common Colored Gemstones
Main highlights

Quick and Accurate Testing
The Presidium Gem Indicator offers fast results in under 6 seconds, ensuring accuracy with its retractable thermoelectric probe.

Ideal for Gem Enthusiasts
Perfect for identifying diamonds and 31 different gemstones, including rubies and sapphires.

Highly Praised for Versatility
Users appreciate its ability to test various gemstones and identify non-gem materials like glass.
9.7

Exceptional

Our Rating

8.0
Simple to use

8.0
worth the money

8.0
Precision
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Value for Money

2

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

Compact Design and Portability
Redesigned to be more compact, sturdy, and portable for easy use.

Ideal for Gemstone Identification
Perfect for identifying diamonds, moissanites, and common colored gemstones.

Reliable Performance
Praised for providing consistent and reliable results in gemstone testing.
9.6

Exceptional

Our Rating

8.2
Simple to use

8.0
Precision

8.0
worth the money
3

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

Compact and Portable Design
Redesigned to be more compact, sturdy, and portable.

Ideal for Jewelry Sellers
Perfect for identifying real stones in jewelry business.

Consistent and Reliable Results
Consistently praised for accurate gemstone identification.
9.5

Excellent

Our Rating

8.4
Durability

8.0
Simple to use

8.0
Precision
4

HMKIS
HMKIS Diamond Tester Pen, Professional Jewelry Diamond Tester with 60X Jewelry Loupe Magnifier, Diamond Selector for Novice and Expert (Non-Rechargeable)
Main highlights

High Accuracy Testing
The diamond tester provides reliable results, distinguishing diamonds from imitations with thermal conductivity.

Ideal for Novice and Expert
Suitable for both beginners and professionals in jewelry testing and inspection.

60X Magnification Praised
Customers appreciate the included 60X LED magnifier for detailed examination.
9.3

Excellent

Our Rating

8.9
movability

8.0
Simple to use

8.0
worth the money
5

SMARTPRO
SmartPro SPGE-I Gem Eye I Gem and Diamond Tester Smart Pro
Main highlights

High Efficiency and Versatility
High efficiency with the thinnest probe tip for precise testing of diamonds as small as 0.01ct.

Ideal for Jewelry Professionals
Perfect for jewelry resellers and gem enthusiasts needing portable, accurate testing anywhere.

Self-Calibrating Feature Praised
Customers appreciate the self-calibration feature, enhancing accuracy despite temperature sensitivity.
9.0

Excellent

Our Rating

8.0
Simple to use

8.0
Precision

8.0
worth the money
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6

GTE
Purity Testing Kit for Diamonds Gemstones Moissanites Gold Silver and Platinum Jewelry Electronic Digital Diamond Tester Machine JSP GTE
Main highlights

Comprehensive Testing Kit
Includes tools for testing gold, silver, platinum, and diamonds.

Ideal for Jewelry Enthusiasts
Perfect for those investing in or evaluating precious metals and stones.

Highly Rated Diamond Tester
Customers praise the diamond tester for its accuracy and reliability.
8.8

Very Good

Our Rating
7

Hqdz
High Accuracy Professional Diamond Tester Pen Jeweler Tool for Novice and Expert - Diamond Selector II 9V Battery Included(Black)
Main highlights

Quick and Precise Testing
Professional Diamond Selector II offers fast, accurate, and safe diamond identification.

Ideal for Home Use
Perfect for checking jewelry at home or small-scale evaluations.

Highly Praised for Accuracy
Customers appreciate its ability to distinguish real diamonds from fakes effectively.
8.7

Very Good

Our Rating
8

Broadsheet
Diamond Tester Professional, High Accuracy Jewelry Diamond Tester Pen, Electronic Diamond Gem Tester and Tester Pen 60X Magnifying Glasses Tool Kit for Novice Expert
Main highlights

Easy to Use and Intuitive Design
Place the tip of the tester on the gemstone; equipped with LED lights and audio instructions for quick results.

Ideal for Jewelry Verification
Perfect for checking the authenticity of diamonds and gemstones in rings, coins, antiques, and other jewelry items.

Accurate and Reliable Results
Customers appreciate the tester’s ability to quickly and accurately determine the authenticity of diamonds, ensuring peace of mind.
8.6

Very Good

Our Rating

8.0
Instruction

8.0
worth the money

8.0
Simple to use
9

Siziviki
Diamond Tester, Diamond Detector, High Accuracy Diamond Tester Pen for Professional Jewelers, Gem Tester (Metal Detection Limitation)
Main highlights

Quick and Easy Testing
Detects authenticity of diamonds, jade, agate, and crystal quickly.

Ideal for Jewelry Verification
Perfect for verifying gemstones in watches and jewelry.

Ease of Use Praised
Customers appreciate its simplicity and effectiveness in operation.
8.5

Good

Our Rating

8.0
worth the money

8.0
Precision

8.0
Simple to use
10

Hqdz
Professional Rechargeable Diamond Tester Pen with UV Light,High Accuracy Jewelry Diamond Tester,Electronic Diamond Gem Tester and Tester Pen-Diamond Selector for Novice and Expert(Diamond Tester Pen)
Main highlights

Quick and Safe Testing
Features an LCD display and LED indicator for easy, precise, and safe diamond testing.

Ideal for Various Users
Perfect for professionals, hobbyists, and business owners needing reliable diamond verification.

Ease of Use Praised
Users appreciate the simple operation and clear results with the diamond tester pen.
8.4

Good

Our Rating

10 Best gem testers of 2025

1

Presidium Instruments Gem Indicator (PGI) Handheld Tester for Identifying Diamonds and Common Colored Gemstones

8.0

8.0

8.0

2

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

8.2

8.0

8.0

3

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

8.4

8.0

8.0

4

HMKIS Diamond Tester Pen, Professional Jewelry Diamond Tester with 60X Jewelry Loupe Magnifier, Diamond Selector for Novice and Expert (Non-Rechargeable)

8.9

8.0

8.0

5

SmartPro SPGE-I Gem Eye I Gem and Diamond Tester Smart Pro

8.0

8.0

8.0

6

Purity Testing Kit for Diamonds Gemstones Moissanites Gold Silver and Platinum Jewelry Electronic Digital Diamond Tester Machine JSP GTE

7

High Accuracy Professional Diamond Tester Pen Jeweler Tool for Novice and Expert - Diamond Selector II 9V Battery Included(Black)

8

Diamond Tester Professional, High Accuracy Jewelry Diamond Tester Pen, Electronic Diamond Gem Tester and Tester Pen 60X Magnifying Glasses Tool Kit for Novice Expert

8.0

8.0

8.0

9

Diamond Tester, Diamond Detector, High Accuracy Diamond Tester Pen for Professional Jewelers, Gem Tester (Metal Detection Limitation)

8.0

8.0

8.0

10

Professional Rechargeable Diamond Tester Pen with UV Light,High Accuracy Jewelry Diamond Tester,Electronic Diamond Gem Tester and Tester Pen-Diamond Selector for Novice and Expert(Diamond Tester Pen)

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