The Voynich manuscript is an illustrated codex, or book, hand-written in an unknown writing system. Vellum is prepared animal skin or "membrane" used as a material for writing on. The vellum on which the Voynich manuscript is written has been carbon-dated to the early 15th century or about 1404 to 1438. It may have been composed in Northern Italy during the Italian Renaissance. The manuscript is named after Wilfrid Voynich, a Polish book dealer who purchased it in 1912.