Charles E. Eichelberger in 1896 discovered a high-grade gold ore body in the Kofa Mountains — also known as the S.H. Mountains — 22 miles as the crow flies southwest of Quartzite.
With the financial support of notable Arizona railroad executive Epes Randolph and H.B. Gleason, the King of Arizona Mining Co. was formed.
The mine christened Gleason was later changed to King of Arizona.
Lack of water for processing ore prompted a five-stamp amalgamation mill and cyanide plant to be built along the Gila River at Mohawk, 35 miles south of the mine site in 1898.
Water deficiency was resolved when a 1,000-foot well dug five miles south of the mine site enabled the operation of an onsite ore treatment mill.
Jaw crushers and rolls dry-crushed the ore loaded into 250-ton vats and leached with a cyanide solution of 4½ pounds of cyanide to 1 ton of water for nine days. Afterward the gold and silver were precipitated in zinc boxes and smelted into bars.
In 1899, Col. Eugene S. Ives acquired the property for $250,000. An average of 125 miners, mostly Cornish, were employed there. Some of the surface ore was valued at $2,000 a ton in gold and some silver.
An old lime quarry with two small adobe furnaces located northwest of Mohawk supplied lime for the Kofa cyanide plant.
An acronym for King of Arizona Mine, or “K of A,” the town of Kofa included a post office created on June 5, 1900. A boardinghouse, saloons, physicians and a school contributed to the model mining community of 300. Crime was minimal and baseball a favorite employee pastime.
Over the next decade production averaged 200 tons a day at $40 per ton. By a depth of 750 feet it dropped to $3 per ton. The mine continued to operate until summer 1910 when the ore body became too low-grade to profitably mine. The mine was developed into an inclined shaft of 750 feet deep with drifts running east and west extending in excess of 2,000 feet. Total production of gold and silver bullion from the Kofa mine was $3.5 million.
Felix Mayhew, a night shift miner at Kofa, developed a mine two miles north of the Kofa Mine in 1906. The North Star Mine included two inclined shafts of 90 and 500 feet totaling 3,500 feet of workings and drew water from the wells of the King of Arizona Mine.
The mine was acquired for $350,000 in 1907 by the Golden Star Mining Co., which built a 100-ton cyanide plant at the mine. The town of Polaris established in June 17, 1909, reached a population of 339 in 1910.
By August 1911 the mine’s profitable ore supply was exhausted, but not before it produced $1.1 million in gold and silver — though it had probably produced more because a portion of the property’s rich ore was stolen by “highgraders.”
Instigated by government buying and premium price programs during the 1950s, the area was mined for tungsten and manganese, producing 230 long tons of low-grade ore and 94 short ton units of WO3.
The Kofa mining district is credited with having produced 779,000 tons of ore including 226,654 ounces of gold, 103,257 ounces of silver, 3.5 tons of lead and one ton of copper. Total production was valued at $4.8 million.
During World War II Gen. George S. Patton conducted military exercises in the Kofa Mountains, leaving behind unexploded ordinance. Today the Kofa district lies in the 665,400-acre Kofa National Wildlife Refuge, including the Kofa and Castle Dome Mountains. Mining activities are prohibited except for valid claims existing before 1974. Narrow and rugged canyons in the Kofa Mountains host desert bighorn sheep along with Arizona’s only known native palm tree population.
Sources: Keith B. Stanton (1978), “Index of Mining Properties in Yuma County, Arizona. State of Arizona Bureau of Geology and Mineral Technology Bulletin 192”; E.L. Jones (1915), “A Reconnaissance in the Kofa Mountains, Arizona.”; Nell Murbarger (1964), “Ghosts of the Adobe Walls”; James E. Sherman and Barbara H. Sherman (1969), “Ghost Towns of Arizona”; Eldred D. Wilson (1933), “Geology and Mineral Deposits of Southern Yuma County Arizona.”
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