27. Gina Rinehart

Company: Hancock Prospecting

Last year’s position: New

Age: 57

Nationality: Australian

Sector: Mining

Location: Australia

The only daughter of the Australian mining pioneer, Lang Hancock, and now chief executive of Hancock Prospecting, Gina Rinehart is almost certainly the richest woman in mining, with an estimated fortune north of $10bn.

She fought hard to get the keys to the chairman’s office, only winning uncontested control of the company after an 11-year legal battle with her stepmother, Rose Porteous, following the death of her father in 1992.

She faced a simultaneous nine-year dispute with the children of her father’s business partner, Peter Wright.

Although Rinehart shuns the social circuit, she is no shrinking violet when it comes to expressing views related to mining. A vehement climate change sceptic, she is also a vocal opponent of the Australian government’s proposed carbon and mining taxes.

In a recent speech to the Commonwealth Business Forum, Rinehart said the introduction of a carbon tax “creates uncertainty at a time when Australia needs to provide certainty to investors”.

She added: “We need to transform ourselves. We need to keep cost competitive. We need to implement special economic zones, to welcome investment, business and people, if we wish west Australia to be a business hub in the 21st century.”