Introduction to Ivory
Introduction
The extremely fine and even texture of ivory has been prized for sculpture and decorative objects throughout history. It is chemically identical to bone and is composed of collagen (protein) and a mineral (tricalcium phosphate).
Tricalcium phosphate chemical's structure. It is also found in rock, and human and animal skeletons.
In India, ivory was used extensively for statues of Buddha and Hindu gods. Ivory has always been considered a luxury item. During the time of Muhammed, it was used widely in pulpits, caskets, as well as doors, furniture, and religious objects. Throughout recorded Chinese history, ivory has been fashionable for jewelry, official tablets, and religious objects. Japanese netsuke, which generally date from 1603 or after, are prized by collectors around the world.
Ivory is often difficult to preserve. It is prone to water and heat damage. It splits and warps readily. When it is buried in soil or rock, it becomes particularly brittle because the laminate degrades. Ancient or deteriorated ivory can be rehabilitated, however. Washing with organic solvents, the use of adhesives, and other techniques are often successful with ivory. Ivory Experts is experienced in evaluating elephant and other ivory, no matter what condition it is in, and we will glad to assist you with its conservation.
Head of a woman, ivory, Assyrian, ca. 800 B.C.; 3.8 cm; visible cracking and damage to top of head; private collection, U.K.
Types of Ivory
Elephant Ivory
The African, or less commonly, Asian elephant is the origin of proper ivory. Ivory comes from the tusks or incisor teeth. The largest African tusks were 8m long and weighed 208 kg. African tusks more typically measure up to 2 m, are about 23 kg in weight. Their typical diameter can be .18 m.
Elephant tusks are hollow for a little less than one half of their length. At the end they have a traverse section with the so-called lines of Owen and Retzius, which look like they are formed by a machine.
Hollow Elephant tusk; image courtesy of Virunga National Park; Congo.
Mammoth Ivory
After it is crafted, mammoth ivory looks almost identical to elephant ivory. But after it ages, it is a different color from aged elephant ivory-typically yellowish, and with a denser surface than elephant ivory. It is often found in deteriorated form because it has been buried, for instance, in Siberian tundra.
Mammoth ivory head of a Cro-Magnum man, 20 cm; found in 1821 in Brno, Czechoslovakia, currently in the Moravian Museum.
Much of the extant Mammoth statuary has been found in Europe, but it had it's origin in Siberia. Siberian ivory is typically a mid-range brown. Many of them are stained with mineral deposits, the result of being buried so long in rocky terrain. Mammoth ivory from Alaska (also known as odontolite) is often turquoise blue.
Walrus
During the tenth through early fourteenth centuries, walrus ivory was quite popular in northern Europe. Trade with Africa was interrupted during this period.
Unlike elephant tusks, walrus tusks are oval rather than round. The ivory is taken only from the male walrus. The tusks are mostly hollow. They have a small cross-section in comparison with that of the elephant tusk.
Walrus typically has a marbled appearance, with a yellowish cast. On the inside, the tusk is filled with a material called "tapioca," it is pitted and thick. Also known as morse ivory.
Walrus Ivory, artist William R. Mann, 6.3 cm.
Pacific Walrus at Cape Peirce, CA; U.S.Fish & Wildlife Service.
Whale
Particularly in the seafaring nations of northern Europe, narwhal horns and whalebone were all substitutes when elephant ivory was unavailable or too expensive. In the narwhal (also known as arctic whale), the left canine tooth can be 2.5 m long. In addition, the teeth of the sperm whale are hollow and easily worked. They were favored by the Inuit over elephant ivory.
Whalebone (also known as baleen) comes from the plates on the roof of the mouth. A rasp is used to take off the rough outer layer before carving. During the eighth and ninth centuries A.D., whalebone was very popular in northern Europe.
Whale tusks and whale bone have been used in the nineteenth and twentieth centuries for scrimshaw, umbrellas, and corsets.
Whale tooth pendant ("Rei Puta") , 18th century, 5.3 inches, Maori, New Zealand.
Hippopotamus
Hippo ivory is white, hard, and extremely shiny. But because hippo teeth are difficult to carve, the objects made from it are usually small. The teeth are angular and covered with an enamel that is nearly impossible to remove.
Hippopotamus scrimshaw; Bighorn sheep, contemporary, David Adams, Inc.
Hippopotamus, National Zoo, Smithsonian Institution, Washington, DC, photograph Jesse Cohen.
Substitutes for Ivory
Trying to come up with a cheaper billiard ball, John Wesley Hyatt (1837-1920) invented a process for making cellulose, the predecessor of plastic. By the late 1860s, Hyatt figured out how to combine cellulose, alcohol, and camphor, and he was able to manufacture objects from the new substance. Dentures were the most popular things made from cellulose in the late nineteenth century. In the 1920s, products like Xylonite, Cellonite, and Pyralin imitated ivory and were used for decorative objects.
In addition, "vegetable" ivory is used for ornament. It comes from certain palm trees native to Brazil and Peru, especially the tagua, also known as phytelephas macrocrapa.
Ivory Techniques
The most commonly used ivory for art is elephant or walrus.
Ivory can be drilled, scraped, sawn and filed.
Ethel Montgomery, Ivory carver at Little Diomede, Alaska, Alaska State Library.
Tusks have an outer layer, which is either (a) cementum (very hard) or (b) enamel (hard). They have a core made of dentine. The dentine is carved.
Elephant tusk morphology, U.S. Fish and Wildlife Service.
After the cementum and the enamel are removed, elephant tusks are ready for use. For example, the tusks can be carved as is or be cut into panels for reliefs.
Panel carved from a single piece of ivory, ca. 1000 A.D; Umayyad Period, Caliphate Spain, Andalusian workshop, 10.8 x 20.3 cm; inlaid with quartz and pigment, Metropolitan Museum of Art, New York.
In the round pieces (carved on all sides) are also made from whole tusks. The hollowness and shape of the tusk prescribe the composition of the sculpture.
Georg Petel; Venus and Cupid; elephant ivory, ca. 1622; 40.5 cm; Ashmolean Museum, Oxford, U.K.
Chinese statues of the Eight Immortals and other religious figures also integrate the shape of the tusk into their design.
Ivory figure with traces of gilding and lacquer, Chinese, 17th or 18th century, Ming or Qing period; 45.7 x 13 cm; Freer Gallery of Art, Smithsonian Institution, Washington, DC.
Tools for working ivory have changed little since Egyptian antiquity, with the notable exception of power tools. In the eighteenth and nineteenth century, the use of lathes for ornamental ivory became widespread. A drill or fly-cutter makes a cut while the object in kept in place, when the ornamental lathe is used. This creates a series of detailed cuts. Today, ornamental lathes can be controlled by computers.
In the fifteenth century, China was indirectly opened to western figure carving through the influence of the Portuguese. The Chinese were exposed to Western taste through the Portuguese in Goa, India, with whom the Chinese traded. In the sixteenth century, the Chinese established ivory carving shops in the Philippines to fulfill Western European and South American demand for carved ivory religious figures. In the seventeenth century, the Emperor Kangxi (1654 -1722), whose reign was one of the most prosperous and peaceful in Chinese history, started an ivory carving factory dedicated to Christian statuettes. Ivory carving for the domestic Chinese market during this time also focused on individual figures.
Kneeling ivory figure from China; traces of original pigment, Seventeenth-century; 3 inches; Los Angeles County Museum of Art, California.
Holtzapffel "Rose Engine" and ornamental turning lathe; c. 1848 rebuilt by John Bower; currently owned by John Edwards, U.K.
Whether you own an object made of authentic elephant ivory or a substitute, Ivory Experts has the experience and knowledge to authenticate and appraise its value.
Please contact Ivory Experts at info@ivoryexperts.com or call us at 1-718-606-4029 for more information.
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