The United States Sesquicentennial coins, a commemorative half dollar and quarter eagle (gold $2.50 piece) for the 150th anniversary of American independence, were struck in 1926 at the Philadelphia Mint. The half dollar depicts George Washington and then-president Calvin Coolidge, making Coolidge the only president to appear on a U.S. coin while living. The National Sesquicentennial Exhibition Commission was chartered by Congress in 1925, and was allowed to purchase and resell for profit 1,000,000 specially designed half dollars and 200,000 quarter eagles. The Commission had trouble agreeing on designs with Mint Chief Engraver John R. Sinnock, and asked artist John Frederick Lewis to submit sketches. These were adapted by Sinnock for the half dollar, without giving credit to Lewis, whose involvement would not be generally known for forty years. The maximum number of each coin was struck, with many melted when they failed to sell at a premium. The Liberty Bell reverse for the half dollar was reused by Sinnock, again without giving Lewis credit, on his Franklin half dollar, first minted in 1948. (Full article...)