How the Gold Lock Scanners work

Every metal has a unique magnetic susceptibility profile

 These profiles can be categorized into a magnetic ordering characteristic (e.g. ferromagnetic, paramagnetic and diamagnetic). Gold Lock’s Internal Coin Scanner (ICS) capitalizes on this phenomena to detect tungsten in precious gold. Ferromagnetism is the basic mechanism by which certain materials such as iron form permanent magnets. Paramagnetism is where certain materials are attracted to an external field but will not be permanently magnetized. Tungsten is as example of paramagnetic material with a strong positive magnetic susceptibility of 8.44. Diamagnetic materials create an induced magnetic flux in the opposite direction of an applied magnetic field. Diamagnetic materials are repulsed by magnetic fields. Diamagnetic force is the opposite of paramagnetic force and has a negative value. Examples of paramagnetic metals are gold (-3.44) and silver (-2.38).

Metallic magnetic susceptibility values:

Palladium: 79.0
Platinum: 25.7
Tungsten: 8.44
Copper: -0.96
Silver: -2.38
Gold: -3.44 

Positive values are paramagnetic and are attracted. Negative values are diamagnetic and are repulsed. Direction of magnetic fields are also opposite in regards to whether the material is paramagnetic or diamagnetic.

SUMMARY: Positive values appear dark when viewed through the Internal Coin Scanner (ICS); negative values appear light. Positive values are attracted to magnetic fields; negative values are repulsed. Tungsten will appear dark in the Internal Coin Scanner even if it is concealed inside a gold coin.