The world’s largest steel maker ArcelorMittal SA said Wednesday it would jointly develop a manganese mine in South Africa in a deal worth $432.5 million.

Keen to secure its own supplies of key raw materials for steel, the company has taken on a series of mining projects in mineral-rich nations.

ArcelorMittal will work with Kalahari Resources and South African state-owned financier Industrial Development Corporation to form Kalagadi Manganese.

ArcelorMittal will have a 50 percent stake in the company which will develop a manganese mine and an ore treatment complex at Hotazel in Northern Cape Province and a smelter complex in Coega in Eastern Cape Province.

The company said drilling in the region has confirmed enough high-grade manganese ore to support the mine for more than 20 years after it starts work in 2010. The Kalagadi region has 80 percent of the world’s known manganese deposits.

Manganese is added to some types of steel to make it stronger.

Kalahari Resources is a majority black-owned company that forms part of a South African initiative to give local people a stake in the country’s rich mineral resources.