The OP coin is a London Mint Sixpence ( no mint letter under the bust) and is First Bust variety with large Crowns on the reverse - S3520 in the Spink book. See https://en.numista.com/catalogue/pieces12966.html
The shadowing effect is not a die error or a double strike but the result of the pressure applied during the striking process. I saw a long explanation of exactly how it occurs on another forum, but I cannot locate it now. It is not uncommon on coins of this age and does not add or detract from the value.
The shadowing effect is not a die error or a double strike but the result of the pressure applied during the striking process. I saw a long explanation of exactly how it occurs on another forum, but I cannot locate it now. It is not uncommon on coins of this age and does not add or detract from the value.























