Salt

From the Roman Catholic rite of preparing holy water. Which contains both water and salt to the Indian custom of using salt on wounds to draw away unhealthy spirits, and with evidence that salt has been used in just that way for as long as humans have employed magic. There is clearly a strong consensus and that tends to be simply based on truth, fact, and experience. Without exception, every civilization on Earth has very similar ideas about the magical properties of salt - namely that it absorbs psychic energy and binds it into its own structure.