High gloss polyester of the modern Asian piano etc probably came in the 60s. But pianos of the 40s would probably have been polished to a fairly high gloss, using hand rubbing methods, with rottenstone (a VERY fine abrasive) as the last step before the polisher. So if true authenticity is wanted, the finish would probably have a higher sheen than many or most satin finishes of today, but it wouldn't look like the thick gloss poly finishes either.
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Fred Sturm
University of New Mexico
fssturm@unm.edu http://fredsturm.net "When I smell a flower, I don't think about how it was cultivated. I like to listen to music the same way." -Federico Mompou
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