This is a special West Point mint American Silver Eagle set issued by the United States Mint. In includes two firsts - the very first "Enhanced Uncirculated" Silver Eagle, and the first "Reverse Proof" Silver Eagle to bear the West Point (W) mintmark.
The "Enhanced Uncirculated" coin is a very beautiful and interesting cross between a satin finish uncirculated coin and a frosted proof coin with a few touches of reverse proof to finish it off. Half of the stripes in the flag and the blue field of the flag draped around the Walking Liberty design are struck with a mirror proof finish, while the remainder of the raised devices are frosted like a proof coin. The entire field of the coin has a satiny near proof-like appearance. NGC has chosen to use SP (Specimen) to describe the “Enhanced” designation given by the U.S. Mint.
The ""Reverse Proof" coin completes the full mintmark ensemble of Silver Eagle mints in Reverse Proof (2006-P and 2011-P, 2012-S, and now 2013-W). It features mirror proof raised devices and satiny frosted 'proof' fields just like all of its reverse proof predecessors.
To learn more about these coins click here to watch a video of MCM CEO John Maben describing this special issue.