It looks like either a die gouge or a bubble under the plating. Easiest way to tell is poke it with a toothpick while watching under magnification. If it moves/flexes at all, it's a bubble, otherwise it could be a gouge.
sorry from your pics it looks like plating issue due to zinc ,don't take my word for it its just an observation from the pics,, thanks cheers
A Die Gouge/Gouge is simply raised metal on a coin. Think in reverse - raised portions of coins are recessed portions of the die - if a tool causes an inadvertent ding/mark/gouge in the die, it will show up on the coin as a raised mark. A bubble can occur on zinc Lincolns where a gas bubble gets trapped under the copper plating due to various reasons, temperature issue, plating issue, mixture issue, etc. The can appear almost identical to a gouge except as noted, if you poke them with a toothpick, the bubble will flex, the gouge won't (since it's solid metal).
Yes, I suppose technically they fall in the Planchet Errors category, although I don't know many folks who actually collect them. Here is some more info for you: http://www.error-ref.com/gas-bubbles/
