If you look at any Silicone, or Silastic products, regardless of
manufacturer they have one thing in common. They yellow under UV
light, so
if there is any sunlight exposed to this mosaic object, get ready for
it to
yellow, radically and obviously. and the surface never gets hard,
always
the rubbery "feel" to it.

Okey, so Silicone yellow under UV light, that is no good.
Well, the Cyprus story was pretty convincing. Searching for Polyester
Resin on danish web-sites are pretty depressing though, it gives me
about 200 matches all about health care regulations and so. I am sure
they have it, they just like to pretend that they don't. I found one
place okey, but the resin wasn't transparent. Any Product Names that
can give me an entrance?