Are you sure it's a gaming token and not a silver souvenir token sold to tourists, Bill? My copy of the O'neal token check list doesn't show a $25 Silver token dated 1993. My list is from 1994 so it's possible Janice added this one later.

There are $28 silver premium tokens from the Nugget, but they should not be dated. Sorry I can't help further.

DonL