The well that I cut inside the book has been lined with white felt that I hand stitched and ribbon embroidered. The white swirls are all Kaisercraft stamps that I heat embossed to give a lovely, opaque finish.
P.S. Hubby loved the end result... he said it's even better now than it was before. Strangely though, there's now a padlock on our glass fronted bookcase. (???)