Paul Kane / Getty Images Easy for her to say. Gina Rinehart, chairman of Hancock Prospecting and listed as the world's richest woman, has put her silver foot in her mouth again, lauding African miners' willingness to work for $2 a day.

An Australian mining heiress who courted controversy last month for suggesting her countrymen were just too lazy to be rich is at it again.

Gina Rinehart, thought to be the world's richest woman, chastised miners for being “too expensive,” saying, “Africans want to work. Its workers are willing to work for less than $2 per day.”

In a 10-minute recording posted on YouTube to the Sydney Mining Club, Rinehart lambasted the domestic mining industry, saying it couldn’t compete in a global marketplace. “Not with Australian prices,” she said. She also railed against the country’s carbon tax and regulatory “red tape.”

But Rinehart’s most inflammatory statement by far was the comparison between Australian miners and those who work in developing African nations. “Such statistics make me worry for this country’s future,” she said.

Rinehart’s remarks drew a sharp rebuke from Australia’s Prime Minister, and it is doubtful that even those African mineworkers would agree with Rinehart’s endorsement of a sub-two-dollar daily wage. Violence flared at a South African platinum mine three weeks ago after workers demanded what media outlet AFP characterized as a near-tripling of their monthly wages to roughly $1,500 (12,500 South African rand).

This isn’t Rinehart’s first jab at Australia’s working class. In a recent article, she wrote, “If you're jealous of those with more money... spend less time drinking, or smoking and socialising and more time working.” That remark touched off its own media firestorm, with politicians and pundits alike pointing out that Rinehart acquired the source of her wealth simply by being born into the right family.

Rinehart inherited privately-held Hancock Prospecting, a company founded by her father. Forbes magazine has listed her net worth at $18 billion as of March.

The Australian press reported that the company made a $225 million after-tax profit on revenue of $738 million in 2009, and that Rinehart was fighting a regulatory order to make public more recent financial records. This isn’t Rinehart’s only legal battle; she is also involved in an ongoing dispute with three of her four children over family assets.

Blaming Australian wages for “uncompetitive” export prices on iron ore is a fallacy, said Gary Burtless, an economist at the Brookings Institution. It oversimplifies in that it fails to take into account better technology and transportation infrastructure and worker skills that could offset higher labor costs or make a smaller number of workers more productive.

Rinehart’s hypothetical $2-a-day workers also might not have comparable education and skills, Burtless pointed out. A report by Australia’s National Institute of Labour Studies for the Minerals Council of Australia predicted that the mining industry will need an additional 86,000 workers by the end of the decade. Prompted by the report, the Council launched an adult apprenticeship program “developed to specifically address the growing shortage of workers in the minerals and energy sectors.”

Burtless said Rinehart also ignored what he called “the most obvious factor that makes Australia an attractive place to do business” — a legal and regulatory infrastructure that protects private property, assets and investments. “They enjoy an outstanding international reputation for fairness and transparency," he said. "For how many countries in Africa can we say the same thing?”

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