Mother of four, Alakija, 62, unseats Winfrey as the richest black woman in the world.
According to Forbes, Oprah Winfrey is worth $2.9 billion. Africa boasts 55 billionaires and they're worth a staggering $143.88 billion in total, according to pan-African magazine Ventures Africa.
Alakija started her career as a secretary in a bank in the mid 1970s. She then studied fashion in London and returned to Nigeria to start a label, Supreme Stitches.
But her biggest break came in oil. In 1993, her company, Famfa Oil, was awarded an oil prospectinglicense, which later became OML 127, one of Nigeria's most prolific oil blocks.
The company owns a 60-per-cent stake in the block, valued at around $7.3 billion, Ventures Africa has reported.
