10 Centimos Parets del Vallès; Cooperativa Obrera La Progresiva

During the Spanish Civil War, the breakdown of small-denomination coinage — hoarded, melted, or simply absent — forced hundreds of Catalan cooperatives, municipalities, and local bodies to print their own emergency scrip. La Progresiva was a workers' cooperative in the small Vallès Oriental town of Parets del Vallès, and this 10 céntimos piece is among the most diminutive emergency issues of the entire conflict. At roughly the size of a large postage stamp, it pushed the practical limits of what could function as circulating currency.

The Generalitat de Catalunya formally authorized local emergency currency in June 1937, giving retroactive legitimacy to issues already in circulation — including many like this one that had been produced months earlier out of sheer necessity.