PORT HEDLAND, Australia — A lanky, dark-haired surfer, Lee Meadowcroft modeled on the runways of London, Milan and Singapore, then followed his dream of going home to Australia to sell herbal medicines. His store failed — he had chosen the wrong street, he says — and he lost almost all his savings. By then, the fashion world had found fresher faces.

So like tens of thousands of other Australians, Mr. Meadowcroft went to the mines.

It was late 2004. He plowed his last $4,000 into a two-week course on how to operate a crane. He found companies so desperate for workers that they would send chauffeured cars to pick up prospective welders, electricians and crane operators and deliver them to the nearest airport for their flights to mining country, here on Australia’s remote northwestern coast.

China back then was growing at a breathtaking pace and needed all the Australian rocks it could get. Mine workers like Mr. Meadowcroft kept a punishing schedule: 13 consecutive days of 12-hour shifts, a day off, then another 13 consecutive days of 12-hour shifts. Mining fueled Australia’s surging exports to China, which at their peak reached nearly $100 billion a year — a figure representing $4,300 for every man, woman and child in the country.

Resource-rich places around the world prospered thanks to China, and Mr. Meadowcroft and his fellow Port Hedland equipment jockeys were no exception. By 2011 he was earning $250,000 a year. He watched idle miners sketch circles in the dust and place cockroaches inside, at times betting more than $100 on which one crawled out first. One welder bought a Ferrari 308 sports car, quickly tired of it and sold raffle tickets for $1,000 apiece to get rid of it.