Indigo-dyed bast fibers on parchment

James Martin <james.s.martin [at] williams__edu> writes

>Has anyone observed blue fibers, or identified indigo-dyed bast
>fibers, on the surface of parchment or leather objects?  We have
>identified indigo-dyed bast fibers on parchment-covered surfaces of
>an object purported to date to 1550.

You do not say where the object was made, but I assume that it is
European in origin.  True indigo, (Indigofera tinctoria) was
probably known in Europe at an early date, but it only began to be
imported regularly after the opening of the Cape trade route in
1560, and was coming in in significant quantities by 1563. The woad
plant (Isatis tinctoria) is indigenous to Europe, was utilised in
classical times, and provided a common artists' pigment from the
13th to 16th centuries.   The pigments from the two species are
chemically identical, and it is unlikely that differentiation would
be possible unless the sample is contaminated with cellular plant
material.

Dr. Nigel Seeley
The National Trust
36, Queen Anne's Gate
London, SW1H 9AS
+44 171-227 4869
Fax: +44 171-976 0747

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                  Conservation DistList Instance 9:52
                  Distributed: Sunday, January 7, 1996
                        Message Id: cdl-9-52-004
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