Original vintage mining magazine ad for E. I. DU PONT DE NEMOURS AND COMPANY, INC. of Wilmington, DE.  Explosives Department.  More Dynamite Per Dollar.  A Group of New Du Pont Extra Explosives Applicable to Quarrying, Mining and Contracting Operations.  Photo shown of North Tunnel.  New York and New Jersey shield of the Holland Vehicular Tunnel, the day prior to their junction.  Booth and Flinn, Ltd., contractors.  Rock obstructions blasted with du Pont Dynamite.  Also shown is the Southern Pacific Railway's cut-off between Black Butte and Grass Lake, OR.  Heiselt Construction Company.  The third photo is The Alaska-Juneau Gold Mining property.  Old two-page 1928 dated coal mining industry advertisement.  Would display beautifully matted and framed!