Answer: A Coin

There is a long standing superstition in many diverse cultures around the world that giving a knife as a gift can bring about a bad change of fortune. Specifically, that fear is that the gift of the blade will somehow sever the relationship between the gift giver and the recipient.

While the origin of the superstition is unclear, the superstitious solution to the problem is rather—if you’ll pardon the pun—clean cut. In countries where the superstition is widespread, knife makers will include a coin with the knife, which is intended to stay with the knife until it is delivered as a gift. The inclusion of the coin allows the gift recipient to immediately give the coin back to the gift giver in “payment” for the knife such that, per the superstition, the gift is not actually a gift but a purchase.