This is not going to be a scientific analysis of this coin,
I have an opinion as to what was done and no idea how it is done.
I bought this coin several years ago as a fake.It is one of several I own,another is 1877S
Trade dollar.A 1916D Mercury
with a added mint mark.For another thread.
The following is what I and the dealer I bought it from believe is a genuine 1889
Morgan dollar with a "CC"mint mark added.
Weight and Diameter are good,"Reeding" looks sharp and clean.Looks like it could have been close to uncirculated,but I
think the whole coin has been buffed,my opinion.


This coin also shows some minor clashed dies on obverse and reverse.

;

These last two pictures,best I could get,show closeup
of "MM" and the fields around it.The coin in hand shows
what appears to be shallow depression to left of "MM"in
field,and a small amount from the right side where I
think meatel was moved to form "MM"."MM" is extremely
rough especially around the top half of both "C's.Looks
like heavy buffing around "MM"area as bottom part of
ribbon,some leaves and Top half of"D"in dollar are smoth
compared to the rest of coin.Also looks like they got the
top left of the"O".

;

All opinions and input appreciated

SsuperDdave let me know on this one,it isn't as sharp as it could be.

regards
coffeecup57