The 1972-S One dollar is part of a series of Eisenhower dollar coins struck from 1971-1978. The specific variety is Silver. Struck in San Francisco and designated as a Business (MS) strike, this coin is made of 40% silver; 60% copper from a mintage of 2,193,056 struck.
Often referred to as "blue Ikes" because they were issued and mailed in blue envelopes.