MEXICO, Estados Unidos Mexicanos. 1917-present. 1/2 Onza 1999 Mo (Silver, 33 mm, 15.55 g, 6 h), Libertad. Ciudad de México (Mexico City). 1/2 / ONZA - PLATA / PURA / 1999 MEXICO Ley .999 Winged Victory holding laurel wreath in her right hand and broken chain in her left, Valley of Mexico in the background and Popocatépetl and Iztaccíhuatl volcanoes in the distance. Rev. ESTADOS UNIDOS MEXICANOS Coat of arms. KM 612. An exceptional well preserved example of this very rare date. Mintage of only 600 pieces. In NGC encapsulation, graded PF 69 Ultra Cameo. Only eight coins graded higher. Proof. This lot can be shipped to a US address.