Every few years I post an update about the Vinland Map (a map, supposedly from the early 15th century, showing part of North America). In 2002 I posted that an analysis of the map's ink proved it was a fake, but in 2003 I wrote that a new study indicated it might be genuine. And in 2004 I linked to a Scientific American article that described historian Kirsten Seaver's theory that the map was created in the 1930s by a German Jesuit priest, Father Josef Fischer, in order to tease the Nazis by "playing on their claims of early Norse dominion of the Americas and on their loathing of Roman Catholic Church authority."
Now a scholar, Rene Larsen of the School of Conservation under the Royal Danish Academy of Fine Arts, says that the map is genuine:
Larsen said his team carried out studies of the ink, writing, wormholes and parchment of the map, which is housed at Yale University in the United States.
He said wormholes, caused by wood beetles, were consistent with wormholes in the books with which the map was bound.
He said claims the ink was too recent because it contained a substance called anatase titanium dioxide could be rejected because medieval maps have been found with the same substance, which probably came from sand used to dry wet ink.
I don't expect Larsen's arguments will end the debate, since the opposing sides in the controversy seem to be pretty well entrenched.