Daguerreotype

I am currently working on a Daguerreotype and am slightly puzzled.
The metallic plate holding the image is contained within what
appears to be its original mount, with a piece of glass covering the
front and adhesive paper securing the back and wrapped around the
sides.  Directly behind the metallic plate, in the mount, is a piece
of strawboard adhered to which is a piece of bright green paper. The
paper is the same size as the metallic plate.  What is the purpose
of the green paper?  Why is there paper there at all?  Is the colour
significant?

If anyone could let me know I would be very grateful as I'm baffled.

Mary Beckett
Social History Conservator
Museum of Welsh Life
National Museums and Galleries of Wales


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                  Conservation DistList Instance 15:21
                  Distributed: Friday, August 31, 2001
                       Message Id: cdl-15-21-010
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