I'm assuming this is bronze, so the HK# is 901. Piece was designed by James Earle Fraser (Buffalo Nickel designer), and were issued to all service members who served between April 6, 1917 and Nov. 11, 1918. This piece was issued with a loop and a ribbon, pieces without the loop are considered rare. If yours was never looped that's a real plus. Hibbler and Kappen had this priced at $35 (without loop) in 1963. So Called Dollars haven't appreciated, for the most part, like most other coins and collectibles, but I would think market price would be higher today. Excellent find!