Paper was once so scarce that monks scraped it clean and wrote over it. Scrolls were hidden in prison walls. Notebooks ended up in the hands of friends who outlived their owners. The manuscripts on this list survived wars, revolutions, theft, and centuries of neglect to become the most valuable handwritten objects ever sold. Some waited a very long time for the world to understand what it was looking at.
#1: The Codex Leicester by Leonardo da Vinci (c. 1508)
Bill Gates paid $30.8 million at Christie’s in 1994 for this 72-page notebook of Leonardo’s scientific observations, written in his characteristic mirror-script Italian. Leonardo theorized about water flow, astronomy, and the luminosity of the Moon. Gates later digitized the pages and released them as screen savers, making a 500-year-old Renaissance notebook briefly part of the Windows 98 operating system.
