Now Available Online: “LEOcode” Compendium of Watermarks and Resource for Coding, Visualizing Handmade Laid Papers

LEOcode is a working compendium of watermarks in the Codex Arundel, Codex Leicester, and other papers of Leonardo da Vinci and is intended to be a research tool for art historians, conservators, and paper/book historians. This website presents the results of an innovative computational approach to enhance, measure, compare, and match pre-machine-made papers through the detailed encoding and visualization of their internal manufactured patterns, including watermarks, chain line intervals, and laid line densities. In addition to identifying papers formed from the exact same mold (moldmates) among Leonardo’s papers, LEOcode provides enhanced photographic images of every available watermarked sheet in the Codex Arundel and the Codex Leicester, as well as free downloadable software for coding and visualizing handmade laid papers. Participation and feedback are welcome! Please direct inquiries to