The knight design is similar, but not right for the Dutch State Ducat (gold coin) of Holland (not the modern country, but the state), while I cannot find any Peruvian issues that do not have text around the Coat of Arms. It is a fob, designed to be hung from a chain, and looks copper, or brass. Interesting, anyways. Probably turn of the Century- 1890's to more probably 1920s.