The Stone Book of Fay, also known as the Lost Book, is an artifact that belonged to Fay.
Exactly how the book came into being or into Fay's possession is unknown. It eventually came into the hands of King Whitson Mariner, being given to him by King Gerard along with the Stone Sword of Flint.
Later, Queen Lillie quotes a passage from the book.
- Smith says he may consider writing a prequel based on Flint and Fay's adventures explaining how exactly Fay got the book, although he asserts that all one needs to know about it in order to enjoy The Green Ember series is in the books he's already written.