Hi Prism99,
Thanks SO much your input. Since purple is my favorite color... This thread has really given me pause to think, as I also have a two door glass paned cupboard under my sewing table full of fabric that gets more sunlight than my bookcase. I will move them to another location and make a curtain or something for the bookcase. I'm guessing if I use fabric as a curtain, then it needs to be something that would not allow light to filter through it?
Karla