10 Céntimos Castellar del Vallès

Castellar del Vallès issued emergency cardboard currency in 1937 as the Spanish Civil War severed normal coin supply chains across Republican-controlled Catalonia. Metal had been redirected toward the war effort, and hundreds of Catalan municipalities were left to print or stamp their own fractional currency to keep local commerce moving. These ajuntament-issued pieces varied wildly in material and execution — cardboard being among the more fragile choices, which explains why intact survivors in presentable condition are consistently harder to locate than their paper counterparts.