I am using handmade paper to form thin papier-mache bowls, and am worried about yellowing.  I gather that latex glue (Copydex) is the worst for this, and also think that wallpaper paste will yellow quite badly, so I have been using thinned PVA.  Does anyone have any words of wisdom for me on this topic?  I do seal my pieces with a spray varnish, but I think it is the light that does it.  I'd really appreciate any comments, as the only other way I can think of to find out about yellowing is to wait five years and check my peices again!

Sue