Alcoa is a vertically integrated aluminum company comprised of bauxite mining, alumina refining, aluminum production (smelting, casting, and rolling), and energy generation. Through direct and indirect ownership, the company has 30 operating locations in nine countries around the world, situated primarily in Australia, Brazil, Canada, Iceland, Norway, Spain, and United States.

Anglo American is a global mining company with a portfolio of mining operations and undeveloped resources. Co. is focused on diamonds, copper, platinum group metals (PGMs), and bulk commodities and other minerals. Co.'s segments include: De Beers, which produces rough and polished diamonds; Copper, which produces copper; Platinum, which produces PGMs; Iron Ore and Manganese, which produces iron ore, manganese ore and alloys; Coal, which produces metallurgical coal and thermal coal; and Nickel, which produces nickel.

Antofagasta is a Chilean copper mining group engaged in the discovery, development and operation of copper mining assets. Co. operates four copper mines in Chile, two of which also produce significant volumes of by-products. In addition to mining, Co. has a transport division that provides rail and road cargo services in northern Chile primarily to mining customers, including to some of Co.'s own operations. Co. is organized into two business divisions based on their products: Mining and Railway and other transport services. The mining division is split by mine and exploration activity. The transport division provides rail cargo and road cargo together with a number of ancillary services.

BHP Billiton is a resources company. Co. extracts and processes minerals, oil and gas, primarily in Australia and the Americas. Co. operates four reportable segments: Petroleum, which is engaged in the exploration, development and production of oil and gas; Copper, which is engaged in the mining of copper, silver, lead, zinc, molybdenum, uranium and gold; Iron Ore, which is engaged in the mining of iron ore; and Coal, which is engaged in the mining of metallurgical coal and energy coal. Co.'s Petroleum unit comprises conventional and unconventional oil and gas assets, and includes exploration, development and production activities.

Medusa Mining is engaged in mineral exploration, evaluation, development and mining or production of gold in the Philippines. Co.'s exploration activities are conducted on, among others: the Co-O Gold Mine; the Tambis project comprising the Bananghilig (B1) Gold Deposit, the B2 Discovery Area, and the Guinhalinan Gold Prospect; the Lingig Copper Project; as well as the Saugon Gold Deposit.

Rio Tinto is a mining group based in the United Kingdom and Australia. Co. is engaged in the business of finding, mining and processing mineral resources. Co.'s major products are iron ore, aluminium, copper, diamonds, coal, uranium, gold and industrial minerals (borax, titanium dioxide and salt). Co.'s activities span the world but are strongly represented in Australia and North America with significant businesses in South America, Asia, Europe and Africa. Co.'s operations comprise four principal product groups - Iron Ore, Aluminium, Copper and Diamonds, and Energy & Minerals.