Yes, your coin has been cleaned. Yes, including that one.

Some may have been, but a great many absolutely were not. When the GSA opened the bags and removed the coins for sale, many of the coins were circulated. There were other bags with mixed dates. There were even Peace dollars mixed in some of the bags in some of the bags, and some of them circulated as well.

What folks are either not aware of or seem to forget is that it was beyond common for the ordinary commercial banks to bag up silver dollars they did not want or had no use for and return them to the mint.

This was because for the entire history of our country the public simply didn't like dollar coins, thus they were never widely used in circulation like cents, nickels, dimes, and quarters. That's why there were so many silver dollars in the mint vaults to begin with. Simply put, nobody wanted them.