Chromic acid

Barry Knight <barry.knight [at] bl__uk> writes

>Cihat Uzun asks about the possible use of chromic acid in
>conservation. I would strongly recommend against this.  Chromic acid
>is very corrosive and toxic and is believed to be a carcinogen.  It
>is harmful to the environment.  It used to be used for cleaning
>glassware in chemistry laboratories, but this was discontinued a
>long time ago, and I can't think of any legitimate use for it in
>conservation.  Don't use it!

I would strongly agree with Barry Knight re the use of chromic acid
in conservation but it does have a use, when combined with nitric
acid, as a detector for metallic silver forming a characteristic
blood red-coloured complex ion.

Simon  Moore MIScT, FLS, ACR
Conservator of Natural Sciences
20 Newbury  Street
Whitchurch RG28 7DN


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                  Conservation DistList Instance 23:36
                  Distributed: Monday, March 22, 2010
                       Message Id: cdl-23-36-003
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