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10 Best diamond testers of 2025
Explore top picks
Best Choice1
PresidiumPresidium Instruments Gem Tester II (PGT II) with Assisted Thermal Calibration (ATC) for Identifying Diamonds/Moissanites and Common Colored Gemstones
9.8Exceptional
Our Rating
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Value for Money2
ValkynosValkynos Professional Diamond Tester Pen with 365nm UV Light & Thermal Sensor – Fast 0.5s Detection, Portable Gem Checker for Novice & Experts – Battery Included
9.5Excellent
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3
HMKISHMKIS Diamond Tester Pen, Professional Jewelry Diamond Tester with 60X Jewelry Loupe Magnifier, Diamond Selector for Novice and Expert (Non-Rechargeable)
Key specs-
Battery:1 9V battery included
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Dimensions:10.16 x 2.17 x 1.38 inches
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Testing Method:Beeping sound alerts
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Sound Alert:Beeping-beeping-beeping
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Weight:4.2 ounces
9.3Excellent
Our Rating
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4
HqdzDiamond Tester,High Accuracy Jewelry Diamond Tester Professional Diamond Tester Pen Jeweler Tool for Novice and Expert - Diamond Selector II 9V Battery Included(Black Diamond Testers)
9.2Excellent
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5
HqdzRechargeable Diamond Tester High Accuracy Diamond Tester Pen with UV Light,Jewelry Gem Tester Pen,Portable Diamond Checker Tool,Professional Diamond Selector for Novice and Expert (Diamond Tester)
9.0Excellent
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6
SizivikiDiamond Tester, Professional Jewelers' Gemstone Detector, High Accuracy Diamond Tester Pen Professional (Metal Detection Limitation)
Key specs-
Battery:9V, not included
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Dimensions:5.31L x 0.87W x 1.57H
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Testing Method:Sound alert above 9
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Sound Alert:Yes
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Weight:3.52 ounces
8.9Very Good
Our Rating
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7
Hqdz-tdDiamond Tester,High Accuracy Diamond Tester Pen＋60X Mini LED Magnifying Jeweler Tool Kit,Professional Jewelry Diamond Selector for Novice and Expert, Thermal Conductivity Meter(Diamond Tester)
8.8Very Good
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8
Hqdz-tdDiamond Tester,Jewelry Diamond Tester Pen+200g/0.01g Mini Jewelry Scale＋60X Mini LED Magnifying, Professional Diamond Selector for Novice and Expert,Thermal Conductivity Meter(Diamond Tester +)
8.5Good
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9
HMKISHMKIS Diamond Tester Pen, Professional Jewelry Diamond Tester with 60X Jewelry Loupe Magnifier, Diamond Selector for Novice and Expert (Non-Rechargeable)
8.3Good
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10
HMKISHMKIS Diamond Tester, Jewelry Diamond Tester, Thermal Conductivity Meter, Can't Test Metal,Must be Operated with Both Hands
8.2Good
Our Rating
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