The 1972 copper-nickel circulating Eisenhower Dollar minted in Philadelphia has three different varieties. I receive many questions about these varieties and so, assuming many more have these same questions but simply do not ask, I am posting this article online for anyone to find.
The difference in the three varieties is most notable in the image of the earth as seen from the moon on the reverse of the coin. The varieties are:
As you can see in the photo, Variety 1 has very distinct features, with 3 islands very clear to the south and east of Florida. The dies that produced this reverse were used to make most copper-nickel Eisenhower Dollars during 1971 and much of 1972.
When this reverse is found on a copper-nickel Eisenhower Dollar, this is the scarce and high-dollar variety of the three. It is easily recognizable due to the near absence of islands below Florida. Instead there are what appear to be ravines in the ocean, and the outlines of the continents are indistinct. The reverse dies that produced this coin were mainly used for the proof coins and silver coins of 1971 and 1972, with a very few copper-nickel circulating coins of 1972 from Philadelphia made with this reverse.
The variety 3 reverse was used in the late part of 1972 for the Philadelphia copper-nickel dollars and for all subsequent years. This one is identifiable by the fact that the three islands below Florida are arranged more directly south, as opposed to those on variety 1 which are off to the east somewhat.