Ed Sutton wrote: > I was unsure about the possibility of lanolin, not sure how much the > cloth has been cleaned. Historically, mild acids were also used to > produce verdigris pigments. Apparently copper can react with just about > anything. There are apparently three copper compounds that are called verdigris; copper carbonate (oxidation in air), copper chloride (salt added), and copper acetate (acetic acid reaction). I suspect we have copper chloride here in piano actions rather than copper acetate because natural animal derived lubricants most likely used at the time seem to me to be more likely to contain sodium chloride (salt) than acetic acid. I wouldn't expect bass strings to react the same unless they were contaminated with a similar lubricant as the flanges. What we see on bass strings is more likely copper carbonate. I realize this won't even slow down the eternal speculation, but it's the only explanation I've ever had that makes any sense to me. Mileage will inevitably, vary. Ron N
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