According to the traces of how they were used, ishisaji is thought to have been used as a kind of portable utility knife to process skin, meat, horns, bone and other animal parts as well as to treat plant materials such as trees and ivy.
用途は使用痕の観察から動物の皮や肉、角や骨など動物質の加工や、木や蔦など植物質の加工など、一種の携帯万能ナイフとして用いたと考えられている。