I found some 190 proof denatured in the garage, at least 15 years old, not sure it can still be purchased, and used that with both 4-0 and 1-0 steel wool. Work well: The dirt and grime floated off revealing nice fiddle and mineral stripes and some shading hidden under 100 years of use. I,ll let it dry for a day or so then steam out the dents. It does not look like it was treated with alkanet oil, no reddish-brown tint, then again I am too inexperienced to say for sure. It is smooth and the checkering cleaned up well with a stif tooth and brass brush. A good learning experience.