Grand Reef Mine

The Grand Reef Mine is nestled in Laurel Canyon on Grand Reef Mountain, near the small town of Klondyke, within the Aravaipa Mining District, Graham County, Arizona, USA. Its exact coordinates are 32° 52' 57'' North, 110° 19' 2'' West, placing it in a remote yet historically rich part of southeastern Arizona. Nearby settlements include Bylas (33.5 km away), Mammoth (35 km away), and others, offering access points for enthusiasts. The mine's proximity to other sites like the Aravaipa Mine and Dog Water Mine enhances its appeal for exploration.

This mine is a treasure for mineral collectors, having produced lead, copper, silver, zinc, gold, molybdenum, vanadium, baryte, fluorspar, and silica. Notably, it hosts 56 valid minerals, including rare finds like Aravaipaite, Artroeite, Calcioaravaipaite, Grandreefite, Laurelite, Pseudograndreefite, and Shannonite, which are type localities (first discovered here). Common specimens include Acanthite, Anglesite, Azurite, Baryte, Chalcopyrite, Fluorite, Galena, and Wulfenite. Production assays from 1915-1920 show 2.83% Cu, 40.9% Pb, 1.4% Zn, 0.01 oz/ton Au, and 20 oz/ton Ag, with total shipping ore of 1,389 tons and concentrates at 2,613 tons.

The mine's geology is fascinating, with a tabular orebody 36.58m long, 9.14m wide, and 234.7m deep, hosted in Pinal Schist and limestone, associated with Horse Mountain volcanics and Goodwin Canyon Quartz Monzonite. The ore is controlled by breccia in the Grand Reef Fault, a vertical sheet striking N12W and dipping 85W, part of a block faulting system trending NNW. The reef itself is over 100ft wide, 200ft high, with an ore shoot 120ft long and 15-30ft wide, offering a rich field for geological study.

Discovered in 1890 and first producing in 1915, the Grand Reef Mine was last checked in 2002 and found inactive. By 1950, it was owned by American Zinc, Lead, and Smelting Co. of St. Louis, Missouri. Workings total over 4,000ft, including a 1,400ft haulage adit and a 300ft winze with three levels at 100ft intervals. Early development reached 300ft by 1890-1900. Known also as Aravaipa Mine, Lead Jewel, and others, it was a significant lead producer, ranking second in Arizona in 1931, with a history tied to the district's challenges with Apaches and outlaws.

Graham County has a warm desert climate, with hot summers reaching 99°F in July and mild winters dropping to 30°F in January, enjoying 284 sunny days per year and low humidity. Rainfall averages 11 inches annually, mostly in autumn, with minimal snow (1 inch/year). Ecologically, it's part of the Sonoran Desert, featuring desert flora like cacti and shrubs. Nearby Mount Graham, over 10,000ft, offers diverse ecosystems, but specific mine-area ecology details are limited, supporting desert-adapted wildlife.

The region includes part of the San Carlos Apache Indian Reservation, reflecting indigenous heritage. Klondyke, named after settlers from the Klondike Gold Rush, adds frontier history. The Aravaipa Mining District's past includes conflicts with Apaches and outlaws, offering a rugged cultural backdrop. While specific mine-related cultural details are sparse, the area's mining and ranching history enriches its appeal for enthusiasts.