Mexican Centenario Obverse; Mexican Centenario Reverse. Mexican Gold Centenario. CALL FOR CURRENT MARKET PRICE 1996, and again from 2000-2009, the Mexican Centenario 50 Peso gold coin contains 1.205 oz. of pure gold. The Centenario is a Mexican gold bullion coin first minted in 1921 to commemorate the 100th anniversary of Mexico's independence from Spain. The coin is not intended to be used as currency; the face value of 50 pesos is for legal purposes only, and does not reflect the actual value of the gold content. Buy 50 Peso Mexican Gold Coins online,.900 pure in varied condition. coin, which is known to many numismatists as the gold Centenario. Bears a face value of 50 Pesos backed by the federal government of Mexico.