The Grolier Codex is a Mayan document that first appeared in the public eye in the 20th century. The codex consists of a fragment of a Maya book, containing almanacs of Venus.
Since its appearance there has been much discussion and disagreement over the document's authenticity. Tests in 2007 did not completely clear up questions but recent tests and analysis of the paper, the ink and the style of drawing have proven the document to be from the 13th century.
Read the full story at Once dismissed as fake, Maya calendar is now proven as Americas’ oldest manuscript, scientists say
Image: Page 6 of the Grolier Codex, depicting a death god with captive. Public Domain