According to the list only two African women are billionaires. They are Isabel dos Santos, the oldest daughter of Angola's longtime president, José Eduardo dos Santos and Nigerian oil magnate Folorunsho Alakija.

Isabel dos Santos, 43, made her fortune from investments in Angola's state oil firm while 66-year-old Folorunsho Alakija made the vast majority of her wealth from oil exploration.

Read below how these inspirational women amassed their fortune;

Isabel dos Santos - Real Time Net Worth As of 3/8/17 = $3.1 Billion

Isabel dos Santos is the oldest daughter of Angola's longtime president and, by virtue of her investments in Portugal and Angola, Africa's richest woman.

Though her representatives deny that her holdings have any connection to her father, President Jose Eduardo dos Santos, FORBES research found that he transferred stakes in several Angolan companies to her. In June 2016, he appointed her the head of Sonangol, Angola's state oil firm.

Her assets in Angola include 25% of Unitel, the country's largest mobile phone network, and 42% of a bank, Banco BIC. In Portugal she owns nearly 6% of oil and gas firm Galp Energia (alongside Portuguese billionaire Americo Amorim), and nearly 19% of Banco BPI, the country's fourth-largest bank She is also a controlling shareholder of Portuguese cable TV and telecom firm Nos SGPS (formerly called Zon).

In June 2015, media reported that she spent slightly more than $200 million to buy a stake in Portuguese electric power equipment firm Efacec Power Solutions. In October 2015, four members of the European Parliament publicly called for an investigation into her investments in Portugal, questioning their legality, saying that the method of payment --a transfer of funds by the Angolan government - "raises the possibility the Angolan State is indirectly and illegally financing private investments of his daughter Isabel dos Santos."

A spokesperson for Dos Santos told Forbes that "Isabel dos Santos is an independent business woman and a private investor representing solely her own interests. Her investments in Angolan and/or in Portuguese companies are transparent and have been conducted through arms length's transactions involving external entities such as reputed banks and law firms."

Folorunsho Alakija - Real Time Net Worth As of 3/8/17 - $1.63 Billion

Folorunsho Alakija is the vice chair of Famfa Oil, a Nigerian oil exploration company that has a 60% participating interest in block OML 127, part of Agbami field, one of Nigeria's largest deepwater discoveries. Its partners include Chevron and Petrobras.

Her first company was a fashion label that catered to Nigeria's elite women, including the wife of former military president, Ibrahim Babangida, who awarded Alakija's company an oil prospecting license.