Mining firms, in particular, face several lawsuits, which South Africa's president, Thabo Mbeki, says he does not support.

ECONOMIST: From a royalties bill, the strong rand and lawsuits

He is the face in China of mining giant RAG and heating systems firm Viessman, appearing on billboards and print ads.

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While the number of migrant workers in China rose 3.9% last year, manufacturers face stiff competition from construction, mining and other industries for staff.

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