Hagstones are stones that have a hole running all the way through them, and are usually found in streams or rivers, and at the seashore, where running water has created the hole in the stone.
This may be one of the reasons why they are considered so powerful, as it is a common belief that magick cannot work on running water, and these stones have been holed by running water and so retain that influence of protecting from magick. A Hagstone Hagstones are also known as Holy Stones, Holey Stones, Ephialtes Stones, Wish Stones, Nightmare Stones and Witch Riding Stones.
They were ascribed with the power of protecting people and animals from the powers of evil spirits and witches, and were often worn around the neck, or hung on the key or door to the cattle stalls or stables. Hagstones were also thought to have the property of preventing milk curdling during a thunderstorm, when evil spirits were most active. This practice continues today in parts of Britain
and Europe. In some parts of Europe farmers milked their cows so that the milk passed through a hagstone.
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