Jan 21 (Reuters) -
* Moody's places 12 mining companies in the emea region on review for downgrade
* Moody's on emea mining co- strong US dollar is a factor contributing to
weakening demand,driving prices lower since most metals are traded in dollars
* Moody's on emea mining co- effect of slowing growth in China indicates a
fundamental change that will heighten credit risk for mining companies
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