John K Jordan
GC, sorry, I can't begin to answer your question but do have a comment about putting something on the surface to see what it would look like with some finish. I use naphtha for this, dries quickly, does not raise the grain, and leaves no residue. I typically remove it from the lathe first and wipe it on with a piece of paper towel.
Wetting the surface has two other advantages: 1st, when still wet I can move the piece so light hits it a different angles and any turning defects like ripples or high/low spots in the center are obvious. 2nd, as the wet surface gloss goes away but before the naphtha evaporates any remaining scratches are usually far easier to see than when dry.