James B. Longacre’s initial L can be seen on the reverse ribbon. It was added to the design during the year as a design change.
Three distinct die marriages have proven the existence of proof strikes of cents. Heritage writes that this is the Snow PR2 pair. It "is characterized by Liberty's long obverse diagonal mark on Liberty's neck at the rear crease under the ear" and "A few prominent die lines on reverse run diagonally upwards from two outside-left Olive leaf tips at 8:45 toward the rim."
Richard Snow and other researchers help collectors to understand Proof cents. There were only 10 to 20 Proof 1864 Indian Head L on Ribbon cents struck in 1864. Restrikes were struck later to meet the needs of collectors. The initial delivery of 10 was around 1871.
Heritage says, "Snow is credited for the discovery of the reverse die [a restrike] that matches the regular-issue Proof Dies of that year . Although the 1869-1871 proofs are struck from older die states, the unique die lines on this reverse match those of proofs.