Gilding - A process where each edge of the book is sanded and almost polished before laying on a thin film of gold foil which is transferred to the book edge with a heated silicon rubber roll. Most people think this is for decorative purpose only when the real purpose is to protect the pages from the natural oils of the human hands. Just open an old book and see the discoloration of the pages. Gilding foil is available only in silver and gold, matt or glossy.