Thermal Conductivity

Diamond Tester

Diamond has a much higher thermal conductivity than any of its simulants, and the tester uses this property to identify both mounted and unmounted stones. The instrument is particularly suited to testing small stones that are recessed in their mount.

Consists of:

1. Hand-held probe that is fitted with a miniature heating sensor.
2. A control box containing the associated electronic sampling and indicating circuits.

Procedure:

1. Short pulses of heat are fed to the probe's silver test tip.
2. The electronic circuits measure the rate at which this is conducted away into the gemstone under test.
3. A high rate of heat transference will cause the green light to flash indicating that the stone being tested is a diamond.
4. A low rate of heat transference will cause the red light to flash indicating that the stone is probably not a diamond.

Do's:

1. Always check the tester against the test plate supplied or a known diamond before using it.
2. Always allow the rings to cool before testing them if they have just been removed from the hand.
3. Always test unmounted stones by placing them table down on a test plate and touching the probe to the culet.
4. Always allow two to three second intervals between tests.
5. Always check stones twice.
6. Always return the probe to the holder after use.
7. Allow all stones to stabilize to room temperature.

Don'ts:  

1. Do not hold the stone or the mount with your fingers.
2. Never apply pressure to the probe.
3. Do not allow the tip of the probe to touch the metal mount.

Rely solely on the results of a diamond tester.