The Toquepala deposit is considered to be an example of a copper–molybdenum porphyry deposit.

The deposit is ovoid, extending over a 3.3 x 3.5 km area. Mineralization has been drill tested to about 950 m from the original land surface. Drilling from within the pit base indicates primary mineralization extends for an additional 930 m below the pit bottom.

Mineralization is closely associated with a complex, 1,500 m diameter intrusive centre dominated by four phases of porphyritic dacite plugs, referred to as "T", "Main", "L/M" and "Late", a dacite diatreme and agglomerates, extensive hydrothermal breccias and latite porphyry stocks and dikes.

In the mine area, the Toquepala Lineament appears to control some aspects of mineralization. The lineament is based on the distribution of three porphyry stocks, two breccia bodies, numerous pebble and thin intrusive dikes within the mine, as well as the Cerro Toquepala, Cerro Azul and Totoral breccia pipes, along a 20º azimuth. The lineament is controlled by a north–northeast-trending pre-mineral fault system.

Mineralization consisted of leached capping, oxide, enriched, transitional and primary mineralization. The first three types have largely been mined out.

Mineralization types included:
• Leached capping was predominantly limonite (jarosite 30%, hematite 60% and goethite 10%) mostly disseminated and in fractures. It is mostly mined out; however, remnants occur around th ........

The Toquepala Operations use conventional truck-and-shovel open pit mining methods.

The open pit mine currently has a circular, conical shape with a diameter of approximately 3.1 km. At present, the highest elevation of the pit walls is on the east wall at 3665 masl. The current bottom of the pit is at 2725 masl, while the depth of the final pit design will be at 2095 masl. Eight pit phases remain in the life-of-mine (LOM) plan, starting with phase 4 and ending with phase 11.

Pit Design Criteria:
Bench height - 15m;
Minimum mining width - 100m;
Ramp width - 37.5m;
Ramp gradient - 8%;
Inter-ramp height - 150m;
Geotechnical berm width - 20m;
Bench face angle - 65 degree;

Mining is conducted using two 12-hr shifts. The mining operations can be summarized as:
• Initial drilling and blasting
• Loading, using shovels, of the blasted material into haul trucks
• Transport of ore and waste, depending on destination to WRSFs, run-of-mine (ROM) leach deposit, leach crusher, and mill crusher.

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