Materials are reported in two categories: raw materials, which are the ore from which we extract product, and associated process materials, which are used in processing but are not part of the final product.
We extract ore, a non-renewable resource, from open pit and underground mines. This ore is either processed through a mill or placed on a heap leach pad to extract the product. In 2016, we processed 54.8 million tonnes (Mt) of ore, compared with 70.7 Mt in 2015.
Associated Process Materials
To process ore and extract metals, our operations use certain materials and reagents such as lime and cyanide, as shown in the table below.
Associated Process Materials and Recycled Input Materials1
Sodium metabisulphite (t)
Grinding balls (t)
Other reagents (t)
Recycled Input Materials
Recycled input materials used at our mines include mainly waste oil, used grinding balls, fly ash and biosolids. These recycled materials are all sourced internally. Recycled input materials as a percentage of our total tracked input materials (excluding raw materials and fuel) remained constant at 4% in 2016.