Khutu

Khutu was the name given to a material used by medieval Islamic cutlers for knife handles. The ultimate source of the material has been a matter of conjecture for more than a thousand years; Islamic polymath al-Biruni was among the first to investigate it and debate about the material—especially its source—continues to this day. The hypothesized sources for the material have included narwhal, walrus, and mammoth ivory, the frontal bones of bulls, goats, and birds, the teeth of snakes, fish, and hippopotamuses, and the root of a tree. The most recent investigation, by natural historian Chris Lavers, has pointed to the frontal boss of the horns of the muskox. Khutu has been ascribed properties other than those of a work material. It was, for example, described as an alexipharmic—a property that eventually was attached to alicorn, the supposed horn of the unicorn. Medieval scholarship Abu Rayhan Biruni Islamic polymath al-Biruni (973–1048) was among the first to investigate khutu, which he referred to as al-chutww. He described it as being from the land of the Kirgiz in the northern part of the Turkish territory and mentioned that it was in great demand in Egypt. He noted that the material came in a variety of colours, with yellowish-green being best, followed by those coloured camphor, white, "like the sun", and dark grey. He also mentioned the beliefs that the material came from the forehead of the roc (an enormous bird from Arabic and Persian myths which was said to carry off and eat elephants) or the forehead of a hippopotamus, but did not seem to attach much weight to these ideas, noting that it was much more similar to the frontal bone of a bull or goat. He wrote: "It originates from an animal; it is much in demand, and preserved in the treasuries among the Chinese who assert that it is a desirable article because the approach of poison causes it to exude."