Rinehart is Chairman of Hancock Prospecting, a privately-owned mineral exploration and extraction company founded by her father, Lang Hancock.
She is one of Australia's richest people; with Forbes estimating her net worth in 2019 at US$14.8 billion as published in the list of Australia's 50 richest people; and The Australian Financial Review estimating her net worth in 2019 at A$13.81 billion as published in the Financial Review Rich List.
Forbes considers Rinehart one of the world's richest women.
Rinehart was born in Perth, Western Australia, and spent her early years in the Pilbara.
She boarded at St Hilda's Anglican School for Girls and then briefly studied at the University of Sydney, dropping out to work with her father at Hancock Prospecting.
As Lang Hancock's only child, Rinehart inherited a 76.6% share in the company upon his death in 1992, and succeeded him as executive chairman.
The company's remaining shares were transferred to a trust for her four children.
When Rinehart took over Hancock Prospecting, her total wealth was estimated at A$75 million.
She oversaw a rapid expansion of the company over the following decade, and due to the iron ore boom of the early 2000s became a nominal billionaire in 2006.
In the 2010s, Rinehart began to expand her holdings into areas outside the mining industry.
She made sizeable investments in Ten Network Holdings and Fairfax Media (although she sold her interest in the latter in 2015), and also expanded into agriculture, buying several cattle stations.
Rinehart was Australia's wealthiest person from 2011 to 2015, according to both Forbes and The Australian Financial Review.
Her wealth peaked at around A$29 billion in 2012, at which point she overtook Christy Walton as the world's richest woman and was included on the Forbes list of The World's 100 Most Powerful Women.
Rinehart's net worth dropped significantly over the following few years due to a slowdown in the Australian mining sector, however her fortune remains immense.