Other artifacts excavated on site made of animal, fish, bird, and whalebone, whale and walrus ivory, and killer whale teeth included awls, needles, knives, beads, adzes, shovels, small bowls and, most remarkably, ivory pins up to long. These pins are very similar to examples found in passage graves in the Boyne Valley, another piece of evidence suggesting a linkage between the two cultures. So-called Skaill knives were commonly used tools in Skara Brae; these consist of large flakes knocked off sandstone cobbles. Skaill knives have been found throughout Orkney and Shetland.