Measuring moisture in magnetic material?

I just got involved in a project with a local mining company, and one of
the threads involves measuring moisture content. The people working in the
project claim that there is no good method to measure this "on line" (i e
fast and frequent) when the material is magnetic. Is that really true?
Any suggestions? Assistance would be greatly appreciated.

Robert
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Robert Lundqvist
Dept of mathematics
Lulea University of Technology
Sweden

http://www.math.ltu.se/~robelu


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