Not at all. That means your coin was minted in Philadelphia. There's a list of values available at many sites; for ex. http://www.numismedia.com/fmv/prices/mordlr/pricesgd.shtml
Until 1979-80, Philadelphia coins did not carry a mint mark. The only exception was during WW2 when nickels carried the "P" mark due to a composition change to save metal for the war effort.
In 1979 the Mint decided that Philadelphia coins should also all have mint marks. The "P" mark was added to dollar coins in 1979 and to all others except the cent in 1980. It was decided to leave the P mint mark off the cent because small numbers of cents are sometimes struck at San Francisco and/or West Point when demand warrants. The Mint did not want to create artificial rarities versus the enormous quantities struck at Philadelphia and Denver
A rare Morgan Silver Dollar is 1876.
The Morgan silver dollar is a collectors item and can be about $39
Neither. The Morgan silver dollar is 90% silver, 10% copper.
An 1879 "Silver Dollar" is a Morgan dollar.
The Morgan dollar is 90% silver, or contains about .77 troy ounce of pure silver.
A Morgan dollar IS a silver dollar. The term Morgan refers to the designer George T. Morgan who created the images used from 1878 to 1904 and in 1921.
A Morgan 1882 Silver Dollar has 0.7735 of an ounce of silver.
coz it ain't a Morgan silver collar
George T. Morgan
Exactly one. A Morgan dollar is a specific kind of silver dollar, designed by and named for George T. Morgan and minted from 1878 to 1904 and in 1921.
The Morgan Silver Dollar can range from $25 to $70, and the Peace Silver Dollar from $50 to $300.
A Morgan Silver dollar is 38.1 mm in diameter and 26.7 gm in weight.