Glass spheres on painting

I am treating an early 20th century oil-type painting on canvas
which the artist decorated by adhering small half spheres of colored
glass to the surface (several colors, and 3 sizes, 17 mm, 9 mm, and
6 mm diameter). Some of the half spheres are lost, and the curator
prefers me to replace them with something that looks the same (just
inpainting is not an option). I can imagine casting replacements by
adding color to a clear resin, perhaps epoxy of some sort. Does
anyone know of a casting material that looks like glass and won't
noticeably discolor over time? If so, how would you recommend adding
transparent color to it? If not, are there any other suggestions for
how to replace the spheres? I'm afraid it could be hard to match the
colors well enough by ordering glass spheres ready-made.

Janine Wardius
Malerikonservator/ Paintings Conservator
Bergen Kunstmuseum
Rasmus Meyers Alle 3
N-5015 Bergen, Norway
+47 5556 8044


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                  Conservation DistList Instance 25:46
                  Distributed: Sunday, April 15, 2012
                       Message Id: cdl-25-46-010
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