From card: "Wooden rod rests against long edge stone & held to it by raw-hide (buffalo) being sewed around it and passing around bottom of stone (see attached card for use) At handle end is a loop, to which originally was suspended a bunch of hair (buffalo, horse, etc.) which might be used to wipe blood from hands. This instrument was given to Capt. C. B. Thompson, U.S.A. by a Sioux ... [woman]. It is called a skull-cracker, and was used in numerous wars. After a battle, it was the custom of the Sioux women to search the field, and if an enemy were found in whom life was not extinct, to crack his skull."