Lang Hancock daughter set to overtake Carlos Slim, Bill Gates as world's richest: Citigroup Australia's richest woman, Gina Rinehart, owns her companies outright and does not have shareholders. NEARLY 20 years ago, a young Australian widow inherited a debt-ridden mining company from her father. Today Gina Rinehart, 57, is the richest person in Australia and predicted to become the wealthiest in the world. She saw her fortune more than double to $10.3 billion in the past year thanks to a commodities boom, and is on course to overtake both Mexican magnate Carlos Slim, who is worth ₤46bn ($70.1bn), and Microsoft chairman Bill Gates (₤35bn), according to Citigroup. While Ms Rinehart's wealth is now only a fraction of theirs, researchers at the US financial group calculate that three coal and iron ore projects she is developing will eventually catapult her into the lead, not least because she owns her companies outright and does not have shareholders. After viewing the Citigroup research, SmartCompany, an Australian business website, said: "If Rinehart was a company listed on the (Australia Stock Exchange) and valued using the same 11-times price-to-earnings ratio as her partner, Rio Tinto, she would be worth $US30bn ($28.65bn), putting her in the top 10 of the Forbes rich list. "It is possible to see Rinehart's portfolio of coal and iron ore production spinning off annual profits approaching $US10bn," giving her a "personal net worth valuation of more than $US100bn," it said. Yet, unlike Mr Gates and others in the billionaires club, Ms Rinehart's name is famous mainly among her peers. She shuns publicity and is rarely seen on Australia's social circuit. In her few public appearances she resembles a well heeled rancher's wife more than a fabulously wealthy businesswoman. Last year, she surprised many in a rare appearance at a Perth rally that protested against a mining tax, clambering on the back of a lorry and screaming "axe the tax." To those who did not know her, the only clues that the woman shouting through the loudhailer was anything more than a raucous protester were the huge pearls around her neck. Groomed from the age of 12 to take over from Lang Hancock, her adored father, Ms Rinehart grew up knowing that her future lay literally in the dust. In 1952, two years before she was born, Mr Hancock discovered the world's largest iron ore deposit in Australia's Pilbara region, and as a teenager - while her friends were making their first foray into the world of make-up and pop stars - the young Gina was already being coached on the details of her father's vast holdings. She married twice, first to Greg Hayward, a taxi driver, with whom she had a son and daughter, and then to Frank Rinehart, an American lawyer. They had twin daughters before he died in 1990. Ms Rinehart's hackles rise when she is described as an "heiress," and she insists that she turned the company into what it is today.