Holey Stone

A holey stone is any stone with a hole worn naturally through it, by erosion, wind, waves, sea creatures or other means; it is defined by the hole, not by what it is made of, so it has no formal name. Wikipedia, under the name adder stone, says such stones are usually glassy and most often of flint, that archaeologists have found them in Britain and Egypt, and that they are common on the North Sea and Baltic coasts of northern Germany. British names for them include hag stones, witch stones and fairy stones, and old stories held that they were hardened serpent saliva or came from an adder's sting; Pliny records the Druids prizing a serpent's egg of this kind. Cunningham calls them receptive and gives them to water, linking them with Odin, who in the Eddas slipped through a hole in a rock as a worm to steal the mead of poetry. He records them hung on the bedpost or, in England, tied with red ribbon over the bed against nightmares, worn or hung by the door for protection, and used by English wise women to rub away a child's illness. Looking through one by moonlight is said to show spirits, and in daylight to improve the eyesight.