The study of coin wear is useful for numismatics and economics. We examine a 19th century gold coin with a SEM and show that weight loss is due to a large number of small shocks that follow a truncated power law. Under the compound Poisson process we propose, weight loss over time is nearly deterministic in the proportion of time actually spent in circulation.

中文翻译：

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硬币磨损：小震动的幂律

硬币磨损的研究对于钱币学和经济学很有用。我们用扫描电镜（SEM）检查了19世纪的金币，结果表明重量减轻是由于遵循幂律被截断的大量小冲击所致。根据我们提出的复合泊松过程，随着时间的流逝体重的减少几乎可以决定实际在循环中所花费的时间比例。