Depicts a symbol of both strength and peace—the heraldic eagle with shield, arrows, and olive branch. Purity: American Silver Eagles are .999 fine silver, making these the purest coins ever issued by the United States. Each Silver Eagle contains a full troy ounce of silver, or 31.1 grams, plus copper. The minute amount of copper added enhances the coin's durability and helps it resist scratching and marring.