Series editors' preface - Wood Tools

(a) (b)
Bone and antler
Bone has been used to fill the same functions
as ivory in furniture and the two material types
are often confused. Bone suitable for working
comes mostly from the long bones of
mammals. The outer portions of these bones
are dense, white, relatively non-porous and
readily available around the world from both
wild and domesticated animals. Antlers are the
paired structures found on the heads of male
members of the deer family (Cervidae), such
as deer, elk and moose, that are formed and
shed annually. They evolved from bone and
are therefore very similar to it in composition
and structure.
Bone, unlike ivory, is a living cellular tissue.
It is composed of essentially the same proteins
and minerals as are teeth but, unlike teeth, the
cell nuclei are embedded in bone as it grows
and continue to live throughout the life of the
animal, communicating with each other by
means of tiny canals called canaliculli. Larger
ducts and channels which conduct blood and
fluids are also present in bone and can be
seen as tiny pits and lines with the naked eye.
Like bone, antler shows embedded cell
nuclei and extensive canal networks which
carried blood vessels during antler formation.
Antlers are formed rapidly from randomly
oriented tissue called woven bone as distinct
from the more regular lamellar or layered
bone found in mammalian long bones (Figure
5.5). Antler is most compact in the outer
portions and at the base where it attaches to
Other materials and structures 197
Figure 5.5
(a) Cross-section of an antler (unknown species, 50, visible light). The cell nuclei and vascular canals are present
but have a random structure
(b) Cross-section of a cow bone tibia (62.5, normal light) which has regular Haversian systems of vascular canals
the skull. The interior tends to be spongy or
cancellous and is therefore not generally used
as a decorative material.
Both bone and antler are hygroscopic and
anisotropic, especially in mechanical properties.
Antler is tougher and more elastic than
bone and because of its high collagen content
it is possible to alter the shape of compact
antler by bending it after treating with steam
or hot water.
Ivory substitutes
Vegetable ivory from the hard nuts of the
South American palm Phytelephas macrocarpa
has been used for small carvings and turnings
since the nineteenth century, and has found
renewed favour as a replacement for elephant
ivory among modern craftspeople (Figure 5.6).
Ivory nuts (or corozo nuts) are composed of
virtually pure cellulose, have a slightly warmer
Figure 5.6 Sources of alternative ivory: ivory nut
Phytelephas macrocarpa (1), white tail deer antler and
an unknown species antler tine (2) and cattle horn cup
and tips (3). Item 4 is a piece of hawksbill turtle shell
Eretmochelys imbricata