Johannesburg: New Deputy President Phumzile Mlambo-Ngcuka is best known for engineering a mining charter to give blacks a bigger share in an industry that had exploited them.

Minerals and energy minister from 1999, she ensured that one of the earlier post-apartheid "black economic empowerment" charters soothed investor nerves while sticking to its purpose.

She must now use her skills as a pragmatist to restore unity in the ruling ANC, which has faced a damaging rift since Jacob Zuma was implicated in a high-profile corruption trial, leading to his being fired and charged.

Mlambo-Ngcuka, 49, finds herself thrust into the limelight as the country's first woman deputy president, but has supporters inside and outside the ANC.

"Within government circles, trade unions and large sections of business, she is regarded as the most productive minister, with a record on delivery," the Financial Mail business magazine said of her last year.

Mlambo-Ngcuka is well regarded in the mining sector as firm but fair, gaining top points for successfully concluding the black empowerment charter that in its early stages frightened off investors and wiped billions of rands off the value of mining shares.

"She's known to be very effective," said Susan Booysen, a professor of politics at Nelson Mandela Metropolitan University in Port Elizabeth and an expert on the ANC.

"But the pressures are going to be very significant. There is no mercy in that job."

With acknowledgements to Ed Stoddard and  the Cape Times .