ANTIQUE SILVER MINE BOND BROADSIDE ca. 1870 BUNKER HILL MINING BOND IDAHO. Antique Broadside Bond Certificate–BUNKER HILL MINING BOND, SERIES A. (“The Bunker Hill Silver Mining Company of New York and Nevada”). Bond Printed on paper which is about 21-1/2″ x 26-1/2″. Condition: soiling, toning, fold lines, edge wear. Please see photos for additional condition review. Auctiva offers Free Image Hosting and Editing. Auctiva gets you noticed! Track Page Views With.