Anyone using Arkansas stones for sharpening plane blades?  I just got an old black stone from my dad, and it seems to be pretty fine.  I have been using the sandpaper on a granite tile (scary sharp method) and thought I might try a stone.  The black stones any good?  Supposed to be the finest of the Arkansas bunch...  (Jason Swan)

The Arkansas stone will eventually wear away leaving a concavity which will distort the plane iron.  If it's an older stone, it may already be worn.  Check it with a straight edge before you use it.  I have  resorted to diamond stones which don't seem to wear with heavy usage.  (Ken Rongey)

A black hard Arkansas stone will be roughly 1000 grit. A really good one will be a bit finer.  (Larry Blan)