You might as a last measure try some rubbing compond. There's a type used
by jewelers called "Jeweler's Rouge" and while it is abrasive, you'd have
to get a microscope to see it. But I have used it many times on old guitars
I've bought that have gone dull and hazy from sweat stains or cigarette
smoke, etc. The results are excellent and the wood looks like new, nice and
glossy. There are even some new car cleaners that do essentially the same
job and are easier to find (like at an auto store).
 
Jim Miller
Tallahassee, Florida
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