Chemistry Reference
In-Depth Information
FIGURE 80
Ivory.
Ivory amulet, chalcolithic period, Beer Safadi, Israel. Ivory has been
extensively used for carving decorative objects and ornaments. The ivory of the tusks
of elephants and ancient mammoths has long been valued for its close-grained texture,
hardness, pleasing color, and the smoothness of its surfaces. As early as palaeolithic
times humans engraved representations of animals on tusks. Ivory carving was prac-
ticed in ancient Europe and in Asia. In China and Japan, for example, ivory was used
for making small statues and ornaments of great precision and for inlay work.
walrus, which have been used for making utilitarian and, especially, orna-
mental objects (see Fig. 80). The only source of “true ivory,” however, is the
tusks of elephants and, in ancient times, also of mammoths. Tusks have a
cavity at their base, filled, in living animals, with a mixture of proteins and
fatty material. Unlike most animal teeth, tusks consist entirely of dentine
(ivory), with no outer layer of enamel. Most elephant ivory originates in the
equatorial regions of Asia and Africa. Mammoth ivory, still found in Siberia,
grew in spiral form to lengths of up to 4 m, and each tusk weighed as much
as 100 kg (Kühn 1986; McGregor 1985). A material derived from the beak of a
bird, the helmeted hornbill (
Rhinoplax vigil
) though structurally it is not ivory,
was widely used as ivory in China for many centuries (Kane 1981).
Horn
Horn
is the hard organic material that makes up the horns and hooves of
many mammals, among them cattle, sheep, goats, and antelopes, and the
