The most obvious form of actual money in the form of the Coin made of precious metals is completely irrelevant to the existence of money proper. It is explained solely by the intention to prevent the production of counterfeit money.
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HEINSOHN, Gunnar and STEIGER, Otto, 1996. Eigentum, Zins und Geld: ungelöste Rätsel der Wirtschaftswissenschaft. Reinbek bei Hamburg: Rowohlt. ISBN 978-3-498-02933-3, p. 285.