OK, a quick question. I am not a strike collector but have a couple. I have gotten rid of most of them in trade for chips and am down to 2 (a Harrah's $10 from the mid-90's and the Binion $10 from 1999-2000).

My question is regarding a strike that I used as a card protector (without the case). It has seemed to have lost its shine (as coins do).

Should this be polished, or is that taboo.. and if you do, how do you polish it.