1872 (U.S. Patent Office) 121 (list) Ore stamps.
1876 (U.S. Centennial Comm.) (ed. 2) 27/2 Steel faced ore stamp shoes, and all articles requiring hard cast steel welded to cast iron.
1997 (Nexis) 6 Aug. (Nation section) 1 a Several of the items in the museum were donated or are on loan, including an ore stamp mill built in 1900.