Antique silver flatware was made in sterling silver or was silver plated, which is an application of a thin layer of silver on a base metal. Hallmarking are marks required by law placed on the silver to indicate the maker, date, place of manufacture and/or purity of the silver.
Because silver is too soft for functional use, alloys need to be added. Individual countries established their own silverware standards. Assay offices was created to ensure a coin silver quality level. Between 1792 and 1837, sterling fluctuated between 750/1000 and 900/1000, representing the number of pure parts of silver within each piece of silver.
Not until 1906, through the U.S. National Stamping Act, did all silver marked "sterling" contain 925 parts per 1,000 parts of pure silver.
Recognise silver plated flatware at a glance. Notice the wear as all silver shows signs of wear over time. Silver plate will show areas different in tone. Look for natural areas of wear on raised areas or on spoons and forks where they rest when placed on a table. Silver plate is also a bit heavier than sterling. Most silver plate shows the makers mark only on the back. Rogers Bros. silver plate sometimes marks an "A1," which denotes extra silver has been plated.
Research is required to determine the year the silver plate piece was made. The makers mark gives some clues to the date of the piece, but the real determining factor is the pattern design. Only a few rare pieces of flatware have an actual date. In the case of the marking, 1874 Rogers Bros., this is not the date, but a makers mark. Reference books show the year a pattern was designed.
Turn all pieces of the antique flatware with the face down, so the backs are facing up. Hallmarks can be found on the handle just below the bend of a fork, spoon or knife. The markings are quite small. Use a loupe, with at least a 10x magnification, to look at these markings.
Old European sterling silver will have multiple markings. The marks line up in a row. Every country has a symbol that represents and guarantees a metal content. Another symbol dates the piece. Another symbol is designed by the maker to show his mark. It's common for a European hallmark to show four or five marks in a row.
American sterling silver hallmarks will feature the mark of the manufacturer and the word "sterling." The silver piece can be dated by the style of the makers mark.
Gather all reference books you've found concerning antique silver markings and antique flatware. Many books can be found in your public library. If the library lacks these books, look for online resources. The only way to know when a piece was made or who made it will depend on the success of finding those markings in a book on identifying marks.
There are always exceptions to the rules. In the early years of America, silversmiths struck out European marks and replaced it with theirs. There was also a time where false markings were applied to silver. Continued research and looking for old silver will make for a sharp eye.