Strong, soil-resistant Whitman albums with blue textured leatherette cover are designed with thumb notches for easy window removal. Adolph A. Weinman changed the face of the half dollars with his revolutionary design. Weinman's monogram "AW" appears near the tip of the tail feathers on the reverse of the coin. Liberty Walking half dollars are made of 90% silver and 10% copper. They measure 30.6 mm in diameter, each weighing 12.50 grams. Liberty Walking half dollars were coined at the Philadelphia, Denver and San Francisco Mints.