Australian-based Alumina's Alcoa World Alumina and Chemicals (AWAC) joint venture with Alcoa has signed contracts worth $350m to supply bauxite.
Under the new contracts, which will cover customers in China, Europe and Brazil over the next two years, AWAC will supply the mineral from three of its global mines.
Alcoa Mining president Garret Dixon said: "With our quality resources and deep technical expertise, we are well positioned to deliver a stable supply of bauxite to customers across the global alumina industry.
"Our strategy is to profitably grow our third-party bauxite sales and these contracts demonstrate that we are well on track."
In 2015, Alcoa reported 45.3 million bone dry metric tonnes of production.
Alcoa owns seven active bauxite mines globally and operates four of them, which are located near key Atlantic and Pacific markets, including Australia's Huntly bauxite mine.
The AWAC group of companies is 60% owned by Alcoa and 40% by Australia's Alumina.
Alcoa recently announced that it will separate into two companies in the second half of 2016.
The upstream company will consist of the five business units that make up global primary products including bauxite, alumina, aluminum, cast products and energy.
Another company to be named Arconic will include the global rolled products, engineered products and solutions, as well as transportation and construction solutions businesses.
Image: Bauxite mining at the Huntly mine, WA. Photo: courtesy of Alumina Limited.