How takes place the copper?
Productive processes

1) Geological exploration
Through exploration, ore deposits are identified and characterized; and the ore law is determined as well as the best form of exploitation.

2) Extraction
The mineralized rocks of a suitable size, extracted from the mine (open pit or underground) are loaded and transported to the plant in trucks or train in an efficient and safe manner, to continue with the copper production process.

3) Crushing
From the primary and secondary (or even tertiary) crushing stages, a mineralized material with a maximum size between 1.5 and 1.75 inches is obtained, which is stocked in piles to carry out the leaching.

In three stages, and using large electric crushers, the largest fragments of material coming from the mine are reduced to a size no larger than ½ inch (1.27 cm).

4) Milling
Using the mills, the ore particles are further reduced in size down to a maximum of 180 microns (0.18 mm). With this, a pulp is formed with water and specific reagents, which then goes on to the flotation stage.

5) Flotation
In the flotation cells, a froth is formed in which the bubbles carry up the copper and other sulfide ores contained in the pulp. After several cycles, this froth is collected and dried to obtain the copper concentrate, which goes on to the next production stage.

6) Smelting
In order to separate copper from other ores and impurities, the dried copper concentrate is treated at high temperatures in special furnaces. After several processes, RAF (fire refined) copper is obtained, which is then cast in plates weighing approximately 225 kg, and called anodes.

7) Electrorefination
The anodes coming from the smelter are sent to electrolitic cells to be refined. From this process, high purity or electrolitic copper cathodes are obtained, which are 99.99% copper and weigh between 70 and 80 kg.

8) Leaching
Over the stockpiles of mineralized material, a solution of sulfuric acid is applied, which dissolves the copper contained in the oxide ores, generating a copper sulfate solution which is concentrated before being sent to electrowinning.

9) Electrowinning
The electrowinning process consists of an electrolysis by which copper is recovered from the solution coming from the leaching, and it generates a high purity copper cathode (99.99%).

10) Cathodes
The cathodes obtained from the electrorefination and electrowinning are carefully inspected to ensure quality, and those selected are stocked, weighed and packed to be shipped.

11) Exportation
Cathodes are shipped in trains or trucks to the shipping ports and sent to the clients around the world, with different presence in the continents:

45% to Asia
30% to Europe
14% to Northamerica
11% to Southamerica

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