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How Does a Diamond Tester Work?
A diamond tester is a handheld device that verifies whether a gemstone is a diamond by measuring how it conducts heat or electricity.
There are two primary types of diamond testers:
- Thermal conductivity testers: Diamonds have high thermal conductivity, meaning they transfer heat quickly. When the tester’s probe touches the stone, it measures the amount of heat that dissipates. If the rate matches that of a diamond, the tester indicates a positive result. These are the most common types of testers and rely on the fact that diamonds are excellent conductors of heat.
- Electrical conductivity testers: Some testers include an additional setting to measure electrical conductivity. This feature is especially useful for distinguishing diamonds from moissanite. While both materials have similar thermal properties, moissanite conducts electricity, whereas diamonds generally do not.
Because gemstones have distinct conductivity patterns, testers can help identify or rule out certain materials as diamonds.
Does a Diamond Tester Work on Lab Grown Diamonds?
Yes, diamond testers work on lab grown diamonds. Because lab diamonds are chemically, physically, and optically the same as their natural counterparts, a thermal conductivity test will confirm them as diamonds.
However, the type of tester used and the testing method can impact the results:
- Thermal testers: Lab diamonds pass, as their thermal properties match those of natural diamonds.
- Electrical conductivity testers: These devices may detect inclusions or trace-element differences in lab diamonds, sometimes leading to inconclusive results.
While diamond testers are designed to verify whether a gemstone is a real diamond (whether lab grown or natural) rather than a simulant like cubic zirconia, they are not designed to determine a diamond’s origin. Advanced testing methods, such as spectroscopy or grading reports from certified gemological laboratories, are the most reliable ways to identify whether a diamond is natural or lab grown.
Do Lab Grown Diamonds Test Real?
Yes, lab grown diamonds test as real diamonds because they share the same properties as natural diamonds. As a result, standard diamond testers identify them as diamonds.
However, while diamond testers can confirm whether a stone is a diamond, they cannot determine whether it is lab grown or natural.
