User blog comment:FairyRaven/Fairy Tail Chapter 349: The Demon Doriate, Review and Commentary/@comment-8153438-20130831225050/@comment-7418318-20130901204631

Between Hades learning at least one spell out of it and the Fiore Kingdrom getting information from it necessary to have build the Eclipse Gate I think we can safely assume that it's a real and tangible book.

Or at least was a single book at some point and has probably been copied or ripped apart. I can't imagine Hades and the Fiore Forces to give the respective other one the book after using it or letting it go after no longer needing it.