This amazing necklace is the handiwork of Philly-based Etsy shop The Black Spot Books. It's really quite incredible. She makes these miniature books by hand, using antique and scrap leather for the cover and Strathmore paper for the pages. They're hand-stitched and bound, and are completely usable. She sells a range of other tiny book jewelry, as well as full-sized handmade books. You should take a gander here.