The monarch earned a one-time fee from the original minting of the coin. More specifically, a citizen who brought raw silver to the royal mint left with that same amount of silver now transformed into coin form, less a small part going to the crown. This profit was known as seigniorage. [...] Once a particular coin was produced, however, the king or queen no longer earned revenue from it.
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Short-lived coinage subject to a policy of renovatio monetae was an entirely different manner. Under this model, coins didn't circulate permanently. When a king or queen announced what was known as a renovatio monetae, or a renewal of the coinage, all existing coins had to be brought back to the mint to be recoined into new coins. The monarch collected a fee upon each renovatio monetae.
To help reinforce the monarch's ability to collect a profit, only the most recent coin was allowed to be used within the monarch's domain. Older local coins and coins from other realms were illegal. To distinguish the new version from the outgoing version, the new type was stamped with a different pattern. The penalties for not obeying the rules of renovatio could be harsh. According to Philip Grierson, a numismatist, anyone caught using expired coinage could face imprisonment, a fine, or have their face branded with the old pattern of coin.
The period of time between one renovatio monetae and the next varied widely. In England, the monarch initially adopted an interval of nine years, beginning in 973 AD with Edgar. Later on, this was shortened to just three years. In many parts of Germany and Poland, renovatio monetae occurred yearly, as recounted by economist Roger Svensson in his wide-ranging book on the topic. In the Archbishopric of Magdeburg it was carried out twice a year, coinciding with important market days in the spring and autumn. The Teutonic order in Prussia used a much slower ten-year cycle, according to Svensson.
The date for the switch was often chosen to occur just prior to annual tax payment day or, as in the case of Magdeburg, ahead of a regularly occurring market or festival (see figure above). Requiring that all tax payments or market transactions be conducted with new coins reinforced the necessity of bringing in old coinage to be melted down into new coinage, thus guaranteeing a boost to the monarch's revenues.
The coinage that prevailed in Poland and Germany from the 12th century almost seems to have been designed with a short lifespan in mind, since it is leaf-thin and fragile. Coins minted in this style are known as bracteates, one of which can be seen below. Svensson speculates that the bracteate format was better suited for the purposes of renovatio monetae than standard coins since the costs of periodically reforming silver into thin and pliable coin would have been lower than heavier coins.
From the blog post:
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