[randydance062449]

I would try the absorbent routine first and the solvents last.

Some of the Escher type stones that I have purchased have had a dark, slick, glazed surface. I assume it was oiled. I simply lapped them and it went away. But the oil had time to dry.

So... I would try the absorbent routine first, then the solvents, then let it dry for a month or so and then lap it.

Just my two cents,