Viewing the Pit

Viewing the Pit. . You are looking at the Lavender Pit copper mine. Open-pit mining at Bisbee began in 1917 and ended in 1974. The pit is 4,000 feet wide (north to south), 5,000 feet long, and 850 feet deep at its maximum., Concentrator , Large, circular concrete structures are all that remain of a concentrate thickener, which used a chemical flotation process to separate metal from rock in finely ground ore. The resulting "concentrate" was then shipped to a distant smelter for further processing., Crusher , At the extreme left of the open pit, close to Highway 80, are the remains of the crusher. This machines/crushed large chunks of ore into smaller rocks. A conveyor belt then carried the crushed rock to the mill and concentrator on the hill beyond the pit., Colors , More than 300 different types of minerals are found in the hills around Bisbee. You can spot a few of them around the pit by their colors: , Red - Sulfide minerals that have been oxidized. This rusty-red surface material is found throughout the area. , Gray - Granite porphyry, which contains small amounts of copper. The gray color comes from pyrite in the porphyry. , Yellow - A thin layer of breccia (angular rock fragments embedded in clay) that surrounds the granite. , Purple or lavender - Limestone and conglomerate (rock composed of pebbles cemented together) along the south and east sides of the Lavender Pit. These contain no copper and are considered "waste rock.", Note: The Lavender Pit is not named for the color. It was named after Harrison Lavender, a former Phelps Dodge general manager of Western Operations., Meeting Global Demand: Nearly a century of production in Bisbee yielded some 8 billion pounds of copper. Worldwide consumption of copper is now about 34 billion pounds each year - the equivalent of mining a historic "Bisbee" every three months! (below: Lavender Pit, 2008)