Blank rune

The blank rune is a stone or tile bearing no sign at all, added to the twenty-four runes of the Elder Futhark in many divination sets. It was popularized by the American author Ralph Blum in The Book of Runes, published in 1982, who called it Wyrd and associated it with the unknown and with what is not yet decided. It is also sometimes called Odin’s rune. It appears in no ancient inscription: it is a modern invention, which some practitioners adopt and others reject out of concern for historical accuracy.