Nickel Plate Advertising Piece for S. L. Hart, Jeweler, circa 1900Nickel plate advertising piece featuring S. L. Hart's jewelry business. The front advertises "JAS. BOSS and KEYSTONE NATIONAL", and the back displays "S. L. HART ..JEWELER..EST. 1877". The plate includes a chain. Circa 1900. Found in Ms. Coll. 1410, M, Box 5, Folder 3.