The Mineral Creek district in Pinal county northeast of Florence, Arizona, is an area rich in copper deposits. On November 7, 1846, Kearney's Army, on its way to California and the Mexican-American War, camped near the mouth of a dry creek that runs into the Gila river. They noted the presence of gold and copper deposits, so they gave the creek the name of Dry Creek.

The first mining effort in the Ray area was the Mineral Creek Mining Company in 1880, which eventually became the English-owned Ray Copper Mines, Ltd. They updated the mine, introducing steam tractors, and shipped the ores to Red Rock for processing. Their operation was based on the assumption that the ores were high grade (about 4% copper) and proved to be unprofitable when it was found the ores were running about 2%. They sold their interests in the mine to a group of investors who created the Ray Consolidated Copper Company in 1910. At this time, mining was hard-rock underground mining. In 1933, Kennecott Copper bought the mine and made it the Ray Mines Divison. In 1948, strip mining was introduced, and open pit mining was started in 1952.

Ray, Arizona was a company town that supported workers at the Ray Mines. When Kennecott introduced open pit mining in 1952, the pit eventually encroached on the town. In 1958, residents of Ray, Barcelona and Sonora were moved to the planned community of Kearney, Arizona, named after General Stephen Watts Kearny. Ray no longer exists. More information on these towns can be found at HISTORY OF THE KEARNY ARIZONA AREA

This is a sample of native copper ore from the Ray Mines in the Mineral Creek District.