The coin heavily cleaned and polished, with relief spun.
A rare type from an early, quickly abandoned version of the banner side, the so-called "deep banner".
The presumed change in the type of stamp at the mint was due to technical considerations and the "wedging" of coins in the stamp when struck in the deep version, with fine serrations at the rim. Changing the type of stamp allowed for efficient minting (more on that here).
