At that time proof coins were only struck in Philadelphia, so you cannot have a proof coin from a branch mint. Further, coinage of silver dollars at Carson City was suspended in 1886 and not resumed until 1889.
Please check the coin again and post a new question with additional information. Unfortunately, you'll need to be prepared for the possibility that you have one of the many millions of fakes that have been pouring out of the Far East during the last couple of decades. Many of them are effectively fantasy pieces with impossible dates and/or mint marks (e.g. I saw a "Washington quarter" dated 1865!) but they can fool anyone who isn't up on all the details of mints and years.
There were no 1888-CC Morgam silver dollars minted.
Lowest value would be $15.00 just for the silver.
July 26, 2009 An 1888-S Morgan silver dollar in a good circulated condition [much wear] has a value of about $145. If it is good enough to be almost uncirculated [almost no wear] it has a value of about $300.
Circulated, about $15 apiece.Uncirculated, about $25 apiece.
Assuming the coin is circulated and has no mintmarks, retail value is $30.00-$44.00 depending on how much wear the coin shows. The 1888 Morgan is very common.
There were no 1888-CC Morgam silver dollars minted.
Lowest value would be $15.00 just for the silver.
about $25 depending on condition and mint mark
July 26, 2009 An 1888-S Morgan silver dollar in a good circulated condition [much wear] has a value of about $145. If it is good enough to be almost uncirculated [almost no wear] it has a value of about $300.
A certified example has a average market value of $240.00.
Assuming the coin is circulated and has no mintmarks, current retail value is $33.00-$44.00 depending on how much wear the coin shows. The 1888 Morgan dollar is very common.
Circulated, about $15 apiece.Uncirculated, about $25 apiece.
Assuming the coin is circulated and has no mintmarks, retail value is $30.00-$44.00 depending on how much wear the coin shows. The 1888 Morgan is very common.
It has a value from $65-$11,000 depending on the exact grade of the coin.
Assuming the coin is circulated and has no mintmarks, retail value is $17.00-$26.00 depending on how much wear the coin shows. The 1888 Morgan is very common.
The US didn't print any $1 silver certificates dated 1888. If it's dated 1886, please see the Related Question.
Please look at the coin again. The Carson-City Mint did not issue any Morgan dollars for 1888.