Accounts differ widely on how to make and use a 'black stone'. In Peru, a black stone is a small charred cow bone "applied to the site of a poisonous snakebite and tied firmly in place. It is left there for several days, during which time it supposedly draws the venom from the wound." 13th century Persian/Iranian writer
Kazwini describes the snake-stone in his work
Aja'ib al-Makhluqat as being the size of a small nut.The quote about how the cure goes is as follows "An injury inflicted by a venomous creature is to be immersed in warm water or sour milk. The snake-stone is then dropped into the liquid to supposedly draw out the poison." Although called a 'stone' in the Congo, a black stone is often made from animal bones. When taken from snakes, it is usually from the head, but also said to be extracted from the tail. The steps suggested in an African leaflet are: • Choose a large dry cow thigh bone • Cut it into small pieces • Smooth them with sandpaper • Wrap the pieces in foil • Place in a charcoal fire for 15 to 20 minutes == Views on snake-stones expressed in scientific studies ==