Americans no longer hold claim to the world’s richest people. First, Bill Gates lost the “world’s richest man” crown to Carlos Slim, the Mexican businessman. Now, according to Australia’s BRW magazine, Gina Rinehart – the Australian mining magnate – has become the world’s richest woman. She takes the crown from Wal-Mart heiress Christy Walton, who held the title of world’s richest woman for seven years. According to BRW’s 2012 Rich 200 List, Ms. Rinehart’s net worth is now $29.7 billion. That tops Ms. Walton’s $26 billion pile. Ms. Rinehart’s fortune has nearly tripled over the past year – at the rate of more than $1 million per hour – due to the mining boom in Australia and strong commodity prices. Robert Frank CNBC Reporter & Editor Of course, guessing people’s wealth is usually a guess. And the Bloomberg Billionaire Index lists Ms. Rinehart’s current wealth at a mere $18 billion, putting her well below Christy. So there is room for disagreement. BRW said Ms. Rinehart could become the richest person in the world if commodity prices and Ms. Rinehart’s mining projects continue to grow. (The same boast is being made by Brazilian mining magnate Eike Batista). Yet with her new crown comes anxiety. Ms. Rinehart, as my readers might recall , has been engaged in a vicious battle with her own kids over control of the family business empire. Three of Rinehart’s four kids – John Hancock, Bianca Rinehart and Hope Welker – are suing her to oust her as trustee of the multibillion-dollar family trust established by her late father Lang Hancock. Ms. Rinehart has said that her kids are unfit to run the business. “None of the plaintiffs (her children) has the requisite capacity or skill, nor the knowledge, experience, judgment or responsible work ethic to administer a trust in the nature of the trust in particular as part of the growing HPPL Group,” she claimed in court papers. She is also facing new claims from Aboriginal landowners who say her company isn’t paying them enough for royalty payments. Apparently, it’s not easy at the top – even with $ 28 billion. Do you think Gina Rinehart will ever be the richest person in the world?