To determine the worth of an 1889 silver dollar, have it professionally graded, then refer to a current rare coin pricing guide such as the Official Red Book, or request an estimate from a local rare coin dealer. The American Numismatic Association Certification Service offers a mail-in grading service.
Silver coins have two different valuations. The first value is the melt value, which is determined by the coin's silver content and the current price of silver on the open market. The second value is the estimated market value, or the amount that a coin collector is willing to pay. Coin dealers often offer cash for rare coins, although they usually pay less than private collectors.
The Morgan silver dollar, minted between 1978 and 1921, ranges in value from approximately $20 to several thousand dollars, as of April 2015. The first thing an expert looks for when estimating the value of a Morgan silver dollar is the issuing mint. Morgan dollars were issued from four different mints, and coins struck at Carson City or San Francisco are very scarce. The next major factor that affects a coin's value is the grade or condition. Uncirculated coins garner a premium price, while coins in average or poor condition are priced closer to their melt value.
Do not attempt to clean or polish your coins before they are graded or valued. Cleaning a silver coin lowers its value to both dealers and collectors.