and Arctic North America, mammoth tusks could be recovered from permafrost and used; this became a large business in the 19th century, with convicts used for much of the labour. The 25,000-year-old Venus of Brassempouy, arguably the earliest real likeness of a human face, was carved from mammoth ivory no doubt freshly killed. In northern Europe during the Early Middle Ages walrus ivory was more easily obtained from Viking traders, and later Norse settlements in Greenland than elephant ivory from the south; at this time walrus were probably found much further south than they are today. Sperm whale teeth are another source, and bone carving has been used in many cultures without access to ivory, and as a far cheaper alternative; in the Middle Ages whalebone was often used, either from the Basque whaling industry or natural strandings. Ancient Egypt and Near East The Khufu Statuette may come from the Fourth Dynasty (Old Kingdom, c. 2613 to 2494 BC), when its subject lived, or it may have been carved much later, in the Twenty-Sixth Dynasty (664 BC–525 BC). The MacGregor plaque is more securely dated to around 2985 BC, and may have decorated a royal sandal. Thin ivory plaques were widely used throughout the ancient world as inlays to decorate palace furniture, musical instruments, gaming boards and other luxurious objects. The Tomb of Tutankhamun (1330s BC) contains many such ivory elements, the largest perhaps his carved headrest. The Nimrud ivories are a large group of such objects recovered from a furniture storeroom at the Assyrian capital. They date to around the 9th to 6th centuries BC, and have a number of different origins from around the Assyrian Empire, with the Levant the most common. The so-called Pratt Ivories are another smaller group of furniture attachments from the early second millennium BC, from the Assyrian karum at Acemhöyük in Anatolia. Ivory was used in the Palace of Darius in Susa in the Achaemenid Empire, according to an inscription by Darius I. The raw material was brought from Nubia in Africa and South Asia (Sind and Arachosia). Europe Antiquity and the Early Medieval period Chryselephantine sculptures are figures made of a mixture of ivory, usually for the flesh parts, and other materials, usually gilded, for the clothed parts, and were used for many of the most important cult statues in Ancient Greece and other cultures. These included the huge Athena Parthenos, the