1979 Mexico 1 oz Silver Onza Balance Scale BU (Type III)

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The 1979 Mexican silver Onza represents a fascinating chapter in North American coinage. This specific issue, classified as the Type III variety, is backed by the Mexican government as a sovereign coin. Struck in Brilliant Uncirculated condition, it contains exactly one troy ounce of pure silver, though the total weight of the coin is 33.625 grams due to its 0.925 sterling silver composition. On the obverse, the design showcases an early coin-making apparatus known as a screw press. This mechanical device is surrounded by the inscription "Casa de Moneda de México" alongside the 1979 year of issue, celebrating the rich heritage of the oldest mint in the Americas. The reverse side of the coin displays a classic set of balance scales. It is inscribed with the words "Una Onza Troy de Plata Pura", denoting its status as a single troy ounce of pure silver. Collectors catalog this specific variety under the reference number KM-M49b0.3.