Yes it is.....you can see the stryations in the coin. Worn for sure ,cleaned most probably...yes its a woodie. I love woodies....
Improper Alloy Mix? Yes. Woody? No. Your coin has been cleaned at some point which detracts from its value as a collectible coin. IMO http://www.error-ref.com/improper-alloy-mix/
how are those premiums set just by year and eye appeal? or does the actual improper mix come into play.
My opinion, it's based on collector desirability, and the number of collectors at the time of sale involved in possibly purchasing it and bidding on it. Still it would need to be a "better condition" coin of a respectable grade to make it desirable to serious collectors, then the "woody" collector on top of it adding value for eye appeal get a couple of those chasing a certain date and grade at your auction for their woodie set and it can be run up bidding against each other. Still I don't think they reach "crazy premiums" level, there's a cut off I'm certain. It's not like FSB merc dimes of high grade or FBL franklin halfs, it's an eye appeal thing as a bonus to the condition, and woodies aren't for everyone so it can be hit or miss at gaining additional value in an auction, the buyers need to be there for it.