The U.S. government began purchasing manganese during World War II to compensate for a shortage, due to the number of ships carrying manganese for import that were sunk by enemy submarines. Manganese-buying depots were established in Arizona to enhance production, leading to the discovery of deposits in almost every county.
Manganese is a metallic element used as an alloy to strengthen steel. A minimum of 36 pounds of high-grade manganese ore is required for each ton of steel. Manganese ore itself should carry 35 percent or more of manganese free of such impurities as phosphorous, copper and zinc.
One Arizona depot was established at Wenden in La Paz County, which received more than 200 shipments from mines across the state, equaling about 300,000 tons of crude ore.
The Long Valley mining district, in Coconino County, 56 miles southeast of Flagstaff, was credited with having manganese deposits in Kaibab limestone discovered in the early 1900s. These deposits are 1½ miles west of Clint’s Well, known as the McCloskey group of claims, named for prospector Ben W. McCloskey. Psilomelane was the dominate mineral found in the ore bodies, with small seams of pyrolusite.
The deposits averaged 40 percent manganese, with some shipped as flux to the Clarkdale Smelter along the Verde River. The greatest production occurred during World War II, when $70,000 in shipments were made by rail to the Bessemer furnaces in Alabama.