20 Centavos 0.45 on obverse, billon .450

Chile's billon coinage of the early twentieth century emerged from a prolonged monetary crisis rooted in the suspension of gold convertibility in 1878, which left the country operating on a depreciated paper peso for decades. By 1916, the silver content of the 20 centavos had been progressively debased to the point where the fineness had to be stamped directly on the coin to distinguish it from earlier, higher-grade issues — an unusual concession to public distrust of the coinage itself.

The KM#151.4 designation reflects one of several sub-varieties differentiated by that prominently marked fineness. Casa de Moneda de Santiago was the sole producer throughout this period.