Clearly marked sterling silver and the maker's mark is identified in "Kovels' American Silver Marks" as Simpson, Hall, Miller & Co. (1866-1898). Spoons in sterling silver after were made after 1895. The company was located in Wallingford, Connecticut and later became International Silver Company.
The green star is beside the maker's mark and the red star is beside a letter "D" which would be the year the spoon was made. Unfortunately, my identification book does not give that information.
Source: Kovel, Ralph and Terry. Kovels' American Silver Marks, Crown Publishers, New York, New York, 1961, page 340.
© 2011, copyright Linda Hughes Hiser