Oh my goodness, it's one of the Lewis Chessmen!

Image: Sotheby's

The Lewis Chessmen (previously) are among the biggest draws at the British Museum and the National Museum of Scotland in Edinburgh.They are a group of 12th-century chess pieces, carved from walrus ivory, discovered in 1831 on Lewis in the Outer Hebrides, Scotland. Several pieces are missing. One has just been found in a drawer of an Edinburgh family. Purchased by the family's grandfather for £5 in 1964, it could now fetch £1m at auction.

Lesson learned: go through your junk drawers now and again. You never know what might be lurking there.

More: BBC News