Bronze corrosion

Robert B. Faltermeier <robert [at] faltermeier__biz> writes

>Does anyone have more information about electrolytically corroded
>bronzes? How are these fakes produced, where and what the corrosion
>structure looks like.

I have seen a number of recent fakes of Chinese bronzes which I
believe to have been produced electrolytically or electrochemically.
The corrosion  does not show the deep embayment and intergranular
penetration of natural corrosion.  Lead globules right near the
surface are not affected.  Redeposited copper can be seen near the
corrosion front--usually very finely  divided copper.  Cuprite, if
present, is in tiny spherulites, not massive  crystals.  And
corrosion attacks the alpha (higher-copper) phase first and  leaves
the delta (higher-tin) in place--this is reversed from many (but not
all) ancient Chinese bronzes.  I have just written this up for the
Proceedings of a Symposium on Fakes and Forgeries held by Stiftung
Situation  Kunst in Bochum, Germany last February which is now in
the process of publication.

Tom Chase
Chase Art Services
508 Route 169
Woodstock, CT 06281
860-928-5838


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                  Conservation DistList Instance 21:15
                   Distributed: Sunday, July 8, 2007
                       Message Id: cdl-21-15-003
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