BoM/TWS Message Forum

There's the preface page, one each for the Persona, sealant, Mens, Gluten, the three golem spells, the torn page, the Anima Band, the three components for the Chameleon spell (Chameleon sealant and both interface-related sigils), and then several spells related to the dubious canonicity spells (Imago/Anima copy, Imago/Anima cut, Doppleganger, Imago stripping, Doll, Remote Control, spell 19, Imago Editing, and the swirling lock & key page), so that's at least 22 pages.

The assumption, though, is that the Libra may have more spells deeper down, so there's more pages that haven't been explored. As for its thickness, there's no given width, but it's apparently pretty small because Will can carry it on its backpack without raising alarm. My assumption is that it's no thicker than your typical tabletop RPG splatbook (which is about 1 or 2 inches thick), which would make it pretty inconspicuous. (Then again - isn't that the nature of the Libra in the first place?) There may be forty or even fifty pages, and perhaps most of them would be padding, even unused, or full of a complex sigil whose nature hasn't been discovered yet.

But again, these are assumptions based on the stuff that's been written, so take them with a grain of salt. At best, other than the Anima Band and the Chameleon spell which have seen more use, the established canon is that there's 8 spells, plus the preface.

As a closing statement - consider that the Libra is written in a way where there's hidden content written within the very same pages. All spells up to the Chameleon spell have a reversal sigil, but these can't be accessed except in the rare case where Will gets golemized, when he can see them. These, however, don't add to the page count because they're hidden within the existing pages. There's no given explanation as to why that happens, and one can presume that it's because of hiding the methods to destroy some of the contents OR to save space. It also says that von G wrote the Libra in a way that was extremely space-saving, particularly since his cryptic contents assume the reader's familiarized with magic, so he's summarizing everything in the most laconic way possible.