Identifying chrome tanned leather

Cor Knops asked about (Cons DistList Instance 12:13) a simple method
to identify the presence of a chrome retan on vegetable tanned
leathers. I have been using the ash method for a number of years:
one burns a strip of leather down to ashes; if there's chrome
present it will usually show as pale green among the ashes' black
and grey. Best view on white surfaces.That simple.

Claudius Schettini
Book and Paper Conservator
Philobiblion
Florence, Italy

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                  Conservation DistList Instance 12:16
                 Distributed: Thursday, August 6, 1998
                       Message Id: cdl-12-16-003
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