When Forbes released its 2017 World’s Billionaires list topped by Microsoft co-founder Bill Gates, Australian Mining Magnate Gina Rinehart became Australia's richest person again. She added $6.2 billion to her wealth in the last 12 months, doubling her fortune to $15 billion.

She has the recovery of iron ore price to thank for her return to the top of the Forbes list. Currently ranked No. 69 by Forbes, Gina Rinehart is the only Australian on the top 100 list. Among women billionaires, she is No. 7, although she used to be No. 1 a few years ago.

The spot now belongs to L’Oreal heiress Lilliane Bettencourt whose net worth is estimated at $39.5 billion, according to Forbes.

International market’s impact on list

Ranking in the Forbes billionaires’ list could quickly change, especially for people like Gina Rinehart and other miners whose fortune depends on prices of commodities in the international market. Like Rinehart’s Hancock Prospecting, mining giants BHP Billiton and Anglo American reported in February a surge in profits due to the increase in commodity prices.

As of mid-March, the price of iron ore, one of the key products of the mining ventures of Gina Rinehart, has gone up to $90 from a five-year low of $75 per ton in late 2014. However, she has spread her investments beyond mining by owning shares of Ten television network and purchasing cattle stations in Australia’s north, The Sydney Morning Herald reported.

Generous billionaires

While Gina Rinehart went up in ranking, in the August 2016 list, Forbes removed “Harry Potter” author J.K. Rowling from the list. Her removal was caused by the author’s extreme generosity after she donated $160 million to several charity trusts. She also opened Lumos, her own charity that provides aid to underprivileged children in unfavorable circumstances.

However, having a billionaire status like Gina Rinehart is not important to J.K. Rowling. Like the author, Facebook founder Mark Zuckerberg who ranked No. 5 on the list with a net worth of $56 billion is also generous and has committed to donating to charity 99 percent of his Facebook wealth to charity which he announced in December 2015 after the birth of daughter Max.