Publicidad
Idiomas disponibles
Idiomas disponibles
6
Evaluation and Interpretation of the Results
Measurement principle of the MagneticScreenScale:
The MagneticScreenScale utilizes the different magnetic properties of materials. Materials are
categorized into three classes: diamagnetic materials, paramagnetic materials and ferromagnetic
materials. Ferromagnetic materials are strongly attracted by a magnet. Ferromagnetism is about
1000 times stronger than paramagnetism and diamagnetism. Paramagnetic materials, on the
other hand, are only weakly attracted by a magnet, whereas diamagnetic materials are weakly
repelled by a magnet. This difference between paramagnetic and diamagnetic materials is the
basis for determining authenticity with the MagneticScreenScale. The precious metals gold and
silver are diamagnetic materials and result in a positive value, as the material slightly repels the
magnetic measuring head and thus presses the measuring cell onto the scale. Typical counterfeit
materials such as tungsten, tantalum or molybdenum exhibit paramagnetic behaviour and result
in a negative value, as the material is slightly attracted by the magnet and thus relives the load
on the scale.
Due to the strong magnetic field of the magnetic measuring head, the MagneticScreenScale can
penetrate gold layers of up to 2.5 mm and detect underlying foreign metal cores made of
paramagnetic materials. Please note that the paramagnetism of tungsten, for example, is more
pronounced than the diamagnetism of gold. Therefore, a tungsten layer, which accounts for 40-
50 % of the total weight, can also be detected under a 2.5 mmm thick gold layer. This makes the
MagneticScreenScale a reliable detector for paramagnetic inclusions for commercially available
gold and silver coins and bars weighing up to 250 g. For bars over 250 g, the gold layers can be so
thick that a tungsten core may not be recognized by the MagneticScreenScale. However, in most
of the counterfeits detected, the gold layers were significantly thinner than 1 mm and the
tungsten cores can therefore be detected by the MagneticScreenScale.
28
Publicidad
