The Karst 5.5'' x 8.5'' Stone Soft Bound Notebook is made from high-quality, sustainable, recyclable stone paper with a flexible vegan leather cover. With an expandable back pocket, divider ribbon or bookmark, elastic band and lay-flat binding. This unique, eco-friendly notebook is acid-free, bright white, and waterproof with a premium look and feel. The smooth texture of the 72 sheets of white stone lined pages and flat-lay binding provide ample comfort and writing space for your notes and ideas. This stone paper holds a C2C Cradle to Cradle Silver Certification. That means if you do have to dispose of your Karst notebook; it is recyclable.