Proofhouse.com has serial number lists. As to value, your description leaves a lot to be desired. If its a Single Action Army, it was made the turn of the century. What type of finish (blue, nickel)? Barrel length? Any engraving? You could be in the price range of 100-1200.
if you are taalking about a single action ??? made 1910
depending on the condition between (10%=$750)-(98%=$10,000)
value depends on over all condition. made about 1893
about 1898....................
see text: Iver Johnson Arms and Cycle works 1871 - 1978
made about 1899.....................the value of any firearm depends on condition. i.e. metal finish, grips, bore, etc, etc...............
I assume you colt is a single action revolver ????? if so, made about 1888
1871
value depends on overall condition...................
made about 1907
condition and serial number needed.........
Value of a gun is based on make, model and condition. You gave use year and caliber.