A Chinese Path to Currency Debasement: Xianfeng China’s Overvalued Token Copper Crisis in Comparative Perspective with Europe, 1851–61

This paper develops a transnational comparative framework to analyze an extreme, understudied form of currency debasement: Qing China’s overvalued token coins issued during the Xianfeng era (1851–1861). Whereas canonical European debasements typically reduced weight or fineness of precious-metal coinage through mint monopoly, Qing China issued slightly heavier copper coins at legally inflated nominal values far above intrinsic worth, coupled with mandated payment rules. To make Chinese and European cases commensurable, I introduce the inflated conversion ratio (ICR): the ratio of the weight of standard cash coins that a token coin was legally declared to replace to the token coin's actual weight. By this metric, Xianfeng high-denomination issues (ICR 8.57–60.00) exceed even Europe’s most famous debasement episodes -- Tudor England’s Great Debasement implies an ICR of only 5.88; nineteenth-century European debasements largely fall around 1–2.

The paper builds a model grounded in merchants’ reservation values, a government-imposed mandated payment ratio, market discounting of token coins, and an extension of the quantity theory of money with nonlinear hot-potato velocity dynamics. Crucially, overvaluation induces unauthorized minting, which melted down standard cash and expanded token supply through a logistic response to ICR. Calibrated with Qing monetary and fiscal evidence, the model delivers two core results. First, token-coin seigniorage exhibits an inverted-U: small denominations generate net fiscal revenue, but large denominations collapse once inflation, rising velocity, illicit minting, and enforcement costs erode real gains. Second, when debasement is implemented primarily through administratively inflated nominal conversion rather than metallurgical reduction, fiscal extraction does not scale with denomination and can rapidly become self-defeating.

Historical validation validates these predictions: high-denomination coins were short-lived, while the silver–copper cash ratio rose sharply during 1851–1861 nationwide. My research thus reframes debasement as a regime-dependent fiscal technology, providing a portable metric for systematic China–Europe comparison.