It has also been my experience that flattening  the stone (I use an extra 
coarse diamond plate) will completely clean the  business surface of the 
stone.  No further cleaning is  required.

Cheers,
John

John M. Johnston
There is a fine line  between hobby and mental illness. Dave Barry

In a message dated  12/13/2011 3:42:52 A.M. Central Standard Time, 
pwomack@p...  writes:
If you're going to flatten 'em, I see no need to clean  'em.

Flattening will remove the dirty surface.  

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