| 摘要 |
In order to make metal disks, especially coins, distinguishable and separable from one another and from disks consisting of other materials on the basis of their magnetic properties, they are made according to the invention of one or more nonmagnetic layers, which consist preferably of a copper-nickel alloy containing 5 to 60 percent nickel, and of one or more layers of magnetic metal, especially nickel, in special, very specific thickness ratios between the magnetic layers and the overall thickness of the metal disks in question.
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