Also called holey stone, witches stone, peep stone.
Stone with a natural hole in it. A traditional stone witches carried to enter the otherworld through the hole.
One way to use your hag stone is to slip a short cord through the hole and tie it to your hand during sleep. This will allow dreams to be more vivid and better remembered. You may further enhance this by keeping your stone in a bed of mugwort or other good dream herb.
Varying size but approximately .25 - .75 inch. All have at least one hole through, some have a more than one. Photo shows a variety. Purchase is for one.