Wayne, no hopes; you know very well that, the chances to get the real thing are nihil. And in such case, their sales value, whatever they ask out there, ranging from 50 to 50 000 bucks, is no authenticity reference. It might sound anecdotal but, if you the rub off the verdigris, aren't you destroying lots of the fakers work ? ... sorry the cynicism
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Speaking of their rarity, they have a vast collection of these at the Royal Ontario Museum ... hopefully authentic ones.
(My pictures ... lousy as can be),
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