For many troubled mines, there is no silver lining

Calls that I made recently to three contacts in the coal trading business in Shanxi province and the Inner Mongolia autonomous region went unanswered.

Liu Dongna, an industry analyst, told me that this has happened a lot in recent years as China's coal business has shifted from an industry that created billionaires to one that forced millions of employees to take lower wages or find another job.

"As industry analysts, we often call coal producers, owners of small and mid-sized mines and traders to gather information. A large number of them now cannot be reached," Liu said.