1891 is a common date Morgan dollar with values for circulated coins at $17.00-$36.00
The US has never used a U mint mark. In 1891 Morgan dollars were minted in Philadelphia (no mint mark), New Orleans (O), San Francisco (S) and Carson City (CC). Please see the Related Question for more.
The date of 1891 would make it a Morgan silver dollar. Assuming the coin is circulated and does not have a mintmark, current values are from $25.00-$50.00 depending on the condition (grade) of the coin.
Please post a new question with more information. In 1891 there were 4 denominations of silver coins - dimes through dollars - minted at 4 different mints.
With the dates you listed the coins are of the Morgan Dollar series (1878-1904 & 1921) of US silver dollars and are common. Assuming they are circulated and have no mintmarks, the 1881,1882,1883 coins have the same values of $17.00-$26.00 and the 1891 is a little higher at $17.00-$38.00 depending on condition. Values are a market average and only for coins in collectible condition, coins that are bent, corroded, scratched, used as jewelery or have been cleaned have far less value if any to a collector or dealer.
The 1891 Morgan was struck at all 4 US Mints. S= San Francisco, O= New Orleans, CC= Carson City and no Mintmark = Philadelphia.
The date of 1891 would make it a Morgan silver dollar. Assuming the coin is circulated and does not have a mintmark, current values are from $25.00-$50.00 depending on the condition (grade) of the coin.
There is 24 grams of silver in a 1891 US silver dollar.
Retail values are from $40.00- $70.00 for MS-60 to MS-63 coins which are the most common grades for a uncirculated 1891 Morgan
1891 in Britain was not a Silver Jubilee year for anyone or anything.
Carson City Post Office was created in 1891.
First off, the 1887-CC and 1896-CC are worth about one dollar. Why? Because they are counterfeits! They did not mint coins in Carson City during those years. The only CC Morgan Silver Dollars are from 1878-1885, and again from 1889-1893. The others (if real) are worth between $70 to upwards of $600, depending on the condition of the coin. The 1881 and 1885 are the better of the years listed, as they had less minted.