Silver King Mine

General George Stoneman, desiring an easier access route to Apache strongholds, had ordered the construction of a road from Camp Picketpost into the Pinal Mountains.

A soldier named Sullivan, who was assigned to the construction, discovered some heavy black rocks that flattened when struck.

[3] Mason, joining with Benjamin W. Regan, William H. Long, Isaac Copeland, and another companion went searching for the location of Sullivan's find.

Upon finding the mule, Copeland noticed an unusual rock outcropping and upon closer inspection saw markings that had been left by Sullivan.

The orebody formerly cropped out at the top of a little hill about 75 feet high, composed of heavily-altered yellowish-brown to greenish-gray porphyry.

[10] The operations continued until 1888, when a combination of deteriorating ore quality and lower silver prices prompted the mine to close.

Ore wagons from the Silver King mine at the Pinal mills, circa 1885
Native silver from the Silver King mine, collected prior to 1888.