What this coin looks like (obverse, reverse, mint mark location, special features, etc.): This is the Type 1 1976 S Bicentennial Eisenhower Dollar Proof in Copper-Clad composition. This coin features a 1776-1976 date on the obverse and a portrait of the Liberty Bell in front of the Moon to celebrate the 200th anniversary of the United States of America and President Dwight D. Eisenhower's work in starting the US Space Program which led to the Apollo 11 Moon landings. This coin was produced in both years of 1975 through 1976 so there were no 1975 coins.
There were two major varieties of the 1976 Bicentennial Eisenhower Dollar - Type 1 (Type I) and Type 2 (Type II). Type 1 features bolder and thicker lettering on the reverse of the coin - also struck in a lower relief. Type 2 features sharper and narrower lettering on the reverse of the coin - struck in a higher relief. The difference between the 1976 Type 1 vs Type 2 Bicentennial Eisenhower Dollar varieties is depicted below in the example comparison image:
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