A black and white postcard of the Denn-Arizona Mine. The front caption on the top left reads: “Denn-Arizona Mine. BISBEE, Arizona.” The postcard was postmarked Bisbee, Ariz. June 1st 1910-3:30 PM. and was sent by “Sis” to Kline Ables, Clifty, Arkansas” The message on the back in ink reads: “Hello Kline Am back in Bisbee when to work the mourning with uncle soon. Lovingly, Sis.” The postcard was published by the Albertype Company, Brooklyn, New York.
The Denn mining claim was owned and named after the prospector and hard rock miner Maurice Denn who owned thirteen claims alongside Lemuel Shattuck and Joseph Muheim. The Denn & Arizona copper company sank the shaft in April 1905 and struck an ore body on December 10th 1906 with their efforts hindered by ground water constantly flooding the mine. Pumps were installed to remove the water and the shaft was sunk to the 1000 level. The Denn Mine suffered a severe accident on January 4th, 1907 when four tons of dynamite exploded, leaving a sixty-foot-wide crater and damaging property on the Denn site. Despite the strength of the blast, the miners were fortunate as the resulting casualties amounted to five men injured with no lives lost. When the hassle of removing the water outweighed the value of the ore, the pumps were pulled out and mine shutdown temporarily from 1910 to its reopening in 1917. Miners returned to Denn in December 1917 and in February 1919 they had to deal with a fire that burned out of control for over a week. Copper production at Denn shut down completely when the mine was fully flooded in 1920. In 1925, the Denn and Arizona merged with the Shattuck & Arizona becoming the Shattuck and Denn Company. The copper production improved at the Denn shaft and high quality ore was found at the 1700 level soon after the merger. The deepening of the Junction Shaft allowed for the Denn to drain and reach its full potential. The Denn Mine produced ore for the company from 1925 to 1944. The Phelps Dodge corporation bought out Shattuck and Denn in 1947. After seventy years, the Denn Shaft finally shut down in 1975. Along with copper, the Denn-Arizona mine also produced lead and zinc with smaller amounts of bismuth, gold and silver.