A basic diamond tester generally cannot tell you whether a diamond formed naturally or was grown in a laboratory. Gold Kings recommends treating natural origin as a separate identification question, even when a tester gives a clear diamond indication.
Diamond is a material; origin is another question
Natural and laboratory-grown diamonds share essentially the same chemical, physical and optical properties. That is why an instrument designed to distinguish diamond-like thermal behavior from certain simulants cannot automatically determine origin.
GIA explains that reliable separation requires appropriate specialized equipment or laboratory identification. A simple positive screening result is not that evidence.
Moissanite is a different issue: it is a diamond simulant, not laboratory-grown diamond. Confusing those categories leads to poor equipment choices.
What the store’s testers contribute
The Diamond Mate A, UltraTester 3+ and Duo Tester II have different screening purposes. Compare their documented capabilities individually rather than assuming that any product called a diamond tester resolves every identification question.
The presence of extra lights, additional settings or a more elaborate display does not itself establish natural-versus-laboratory-grown screening capability.
Ask the manufacturer directly whether the exact model supports that task, which samples it accepts and what an inconclusive result requires you to do.
How to check a purchase claim
If a seller describes a stone as natural, request documentation appropriate to that claim. Read the report carefully and verify its number through the issuing laboratory’s official service.
Then make sure the documentation corresponds to the stone being offered. A valid report number alone does not establish that every stone presented alongside it is the reported stone.
For a consequential purchase, use an independent qualified inspection rather than asking a basic tester to settle a question outside its purpose.
Our recommendation
Buy one of the linked instruments when its actual screening role fits your work. Do not buy it merely because you hope a diamond indication will prove natural origin.
If origin is the main reason you are shopping, start by identifying the professional service or specialized instrument that can address it. That can prevent spending money on a useful tool that nevertheless cannot answer your most important question.
Good inspection records should say what was observed, which device was used and what remains unresolved. That is more useful than recording “passed” without explaining the test.
Explore the relevant products
- Presidium Diamond Mate A PDMT-A Diamond Screening Tester
- GemOro UltraTester 3+ Diamond, Moissanite & White Sapphire Tester
- Presidium Duo Tester II PDT II Gemstone Screening Instrument
Check the exact model, seller, package contents and current offer on the linked product page before ordering.
Sources and further reading
Explore more Gold Kings buying guides.
As an Amazon Associate I earn from qualifying purchases. The product pages linked in this article contain Amazon affiliate links. This guide is based on published specifications and practical buying considerations, not a controlled hands-on product test.