The term gilding covers a number of different techniques of applying gold leaf to solid surfaces. Specifically for books, there are a number of different techniques to gild the edges of a book's pages. Roger Grech gives a really good step-by-step guide to rough edge gilding. It would be really cool if I would be able to do this myself when I make my own book in class, but there are too many extra tools needed.
The gold in the gold leaf is usually mixed with other metals or alloys. However, as Beth Carswell says, "not all that glitters is gold," and sometimes it can just be gold-colored paint. Books from the Easton Press gild its pages in 22kt gold.
Taking the gild up a notch is fore-edge painting. This is truly amazing. What looks like normal gold gild turns into a painting.
