Endeavour 22 (E22) and Endeavour 27 (E27) are open cut pits. They have produced ore since November 1993. Each is a large circular hole in the ground, about 500 m across at the top (about the same as the distance across the Sydney Harbour Bridge), and 170 m deep (nearly three times the height above the water of traffic on Sydney Harbour Bridge).
Endeavour 26 (E26) began as an open pit, but is now an underground mine. The entrance to the mine is called the E26 portal. This allows mining vehicles to enter the underground workings and drive down the decline, a 5 m wide tunnel which spirals from the surface to a depth of 480 m (nearly half a kilometre) underground.
After it is mined, the ore is transported on ore conveyer belts to the processing plant. Here is it crushed and ground to a fine powder like flour. The picture shows a giant grinding mill. The finely powdered ore contains valuable bornite and chalcopyrite that are separated from unwanted rock by a process called froth flotation.
 |
 |
 |
During froth flotation, the finely ground ore is mixed with water and detergent-like chemicals. Air is blown through the mixture and a bubbly froth forms on top (see the photo). The tiny grains of valuable copper minerals stick to the bubbles and are skimmed off and dried, to form nearly pure copper-gold concentrate.
The separated copper-gold concentrate is shipped to overseas smelters for conversion into copper, gold and silver metals.
This front-end loader is filling a shipping container on the back of the truck with copper-gold concentrate.
The unwanted powdery rock mixed with water is called tailings, and it is pumped to the either of the two tailings dams for long term storage. This picture shows dried tailings in one of the tailings dams.
 |
 |
 |
