Those 1921 Morgan dollars specially struck for numismatist and Mint friend Farran Zerbe. These Proofs are not of the same quality as the other Proof Morgan dollars. The devices on these specimens usually are not frosted while the fields lack the depth of mirror normally associated with Proofs. In fact, the fields are characterized by heavy die polish, the planchets likely not burnished before striking. (Both Philadelphia and San Francisco examples are known.)