Hunting for Paper Moldmates in Leonardo da Vinci’s Codices

Moldmates are sheets of paper formed one at a time using the same papermaking mold. Due to the manner in which paper was produced before the invention of the papermaking machine, moldmates would naturally be found in the final ream of paper, which would then be procured by an artist. Given their affinity, it can be assumed that paper moldmates share a narrow range of dates and one place of production. Moldmates are identified by matching the patterns that are created by the porous screen of the mold. The areas where the wet paper pulp encountered the wires of the screen as the sheet was being drained are thinner and thus, translucent when held up to light. Often, however, these patterns found within the paper itself are difficult to decipher due to surface marks—writing and drawing—that obscure them.

Speakers: C. Richard Johnson, Jr. (Cornell University), Margaret Holben Ellis (New York University), and William A. Sethares (University of Wisconsin - Madison)