Ivory

national museum of african art conservation lab

Smithsonian

Ivor y National Museum of African Art
Identification and Regulation
of a Precious Material

E lephant ivory has left
been considered Hunting horn
a prized luxury Sapi-Portuguese style,
material across Bullom or Temne peoples, Sierra Leone
cultures from ancient times Late 15th century
to the present day. Artifacts Ivory, metal
64.2 x 16.4 x 9 cm (25 1/4 x 6 7/16 x 3 9/16 in.)
with ivory components have National Museum of African Art, gift of
been found at archaeological Walt Disney World Co., a subsidiary of
sites in Asia, Africa and Europe The Walt Disney Company, 2005-6-9
for at least the past 5000 years.
top
Ivory is a relatively soft material that Elephant in Kabalega Falls National Park, Uganda
can be worked with nonmetal tools, Photograph by Eliot Elisofon, 1966
and its surface can be highly polished, eepa eecl 24872
yielding the characteristic glossy,
creamy and semitranslucent surface above
for which it is much admired. As it Saltcellar
ages it often develops a yellow-golden Benin kingdom, Bini-Portuguese style,
patina. Ivory can be bleached and/or Edo peoples, Nigeria
stained with dyes and colorants. 16th century
Ivory—from the elephants that pro- Ivory
duce it to the intricately carved arti- 8.3 x 7.6 x 7.6 cm (3 1/4 x 3 x 3 in.)
fact—is a material closely associated National Museum of African Art, gift of
with Africa (2005-6-9, 2005-6-36, Walt Disney World Co., a subsidiary of
2005-6-8). Carved artifacts from The Walt Disney Company, 2005-6-36
Africa range in color from bright
white (69-20-4) to a deep red-brown
from the application of palm oils (86-
2-1). In Africa (as elsewhere in the
world), the inherent value of ivory, its
beautiful visual qualities and its ability
to be carved and worked, combined
with royal patronage for the creations
of highly skilled carvers, have yielded
master artworks. Because elephant
ivory is so costly, a number of natural

stephanie hornbeck

Note the difference in coloration; the
figural group derives its dark color from
the application of oils.

left
Spoon
Benin kingdom, Bini-Portuguese style, Edo peoples,
Nigeria
16th to 17th century
Ivory
16.5 x 4.8 x 3.2 cm (6 1/2 x 1 7/8 x 1 1/4 in.)
National Museum of African Art, bequest of Mrs.
Robert Woods Bliss, 69-20-4

right
Staff finial
Kongo peoples, Democratic Republic of the Congo
Late 19th to early 20th century
Ivory, mirror, resin, pigment
13.3 x 5.1 x 5.7 cm (5 1/4 x 2 x 2 1/4 in.)
National Museum of African Art, museum purchase,
86-2-1

and synthetic materials that evoke elephant conservation efforts has re- (In addition to their tusks, elephants
sulted in an international consensus for have six molars that they use to grind
ivory have been used in the creation of ivory regulation. A number of a their food.) Tusks of some African
laws and international agreements males can be up to two meters in
artifacts and art objects (see Ivory instituted over the past 40 years strictly length (6 1/2 feet) and weigh up to 45
regulate its legal trade (see Laws & kilograms (100 pounds) each. Like
Substitues sidebar). Regulations) These have broad teeth, tusks have a pulp cavity where
application and affect museums the root and soft tissue attach it to the
Because elephants do not shed and individual collectors, among other jaw of the animal. The pulp cavity
their tusks while living (as deer shed entities. extends for approximately one-third
antlers), their removal from the ele- of the tusk; its presence or absence on
phant requires the animal to be dead; Description a carved ivory artifact can indicate the
thus, the incessant international part of the tusk that was used and the
demand for ivory has dangerously T he material ivory includes the original length of the tusk. Like teeth,
diminished elephant populations in highly valued tusks and teeth tusks are comprised of dentine and
Africa. It is noteworthy that while of the following mammals: cemen-tum; teeth, however, also have
ivory has historically been prized by mammoths (extinct), elephants, hip- a hard outer layer of enamel, which is
cultures within Africa (perhaps most popotami, warthogs, sperm whales found only at the tip of tusks.
famously by the ancient Egyptians and narwhals. However, this
and the Benin kingdom), internal description focuses on elephant ivory. Identification of Ivory
consumption was limited—often Elephant ivory is the most highly
restricted to royalty—and did not valued of all ivories and describes the W hen considering the
put elephant populations at risk. The material comprising the tusks of Asian question of whether an
establishment of international trade male elephants, African male and object is comprised of
with Africa had dire consequences female elephants, as well as that from elephant ivory, it is useful to gather as
for elephant populations throughout their extinct ancestor, the mam- much information as possible about
the continent. Demand for ivory, moth. It is worth noting that it is the object. Often it is the combina-
variously under trade with the impossible to distinguish between tion of available documentation with
ancient Roman Empire, with India African and Asian elephant ivory methods of examination that will
and the Far East and eventually with visually or by most analytical methods, yield the answer.
Europe and the United States, with the exception of dna analysis.
historically impacted elephant The provenance and age of an ivory
populations in various regions of The tusks of elephants, although artifact may shed light on the geo-
Africa. Demand in the 20th century, differing in function, are directly re- graphic origin of the material, which
however, has seen the greatest lated anatomically and composition-
decimation of African elephants, ally, to the incisors of other mammals.
continent-wide. Consequently, the
intersection of the ivory trade with 2

can narrow down the possibilities for The red arrows against samples and good detail im-
identification. For example, elephants indicate ages of elephant ivory and ivory sub-
are not indigenous to North and Schreger lines, stitutes. The United States Fish and
South America; consequently, ele- ivory’s charac- Wildlife Service (see Selected Biblio-
phant ivory could not have been used teristic unique graphy) has excellent diagnostic
in these regions prior to the establish- pattern of images. The characteristic visual iden-
ment of international trade routes in intersecting tifier of elephant ivory is the presence
the mid-16th century. If the ivory ob- arcs. of a pattern of intersecting arcs
ject was fabricated in the northern- (2004-9-3, 2004-9-2) seen in cross
most regions of Europe, Asia and top section. These arcs are sometimes
North America, it is as likely to be Labret called “engine turnings,” cross-
walrus ivory as elephant ivory. If the Turkana peoples, Kenya hatching or Schreger lines (named
artifact was fabricated after the mid- Mid-20th century after the German anatomist Bernhard
19th century, it could be plastic. Ivory Gottlob Schreger, who first described
5.0 x 5.5 x 3.3 cm (1 15/16 x 2 3/16 x 1 5/16 in.) them in 1800). This pattern is present
The size of the artifact can indicate National Museum of African Art, gift of only on elephant and mammoth
the source of its material. Elephant Eileen Sobeck, 2004-9-3 ivory; obtuse arc angles on elephant
tusks are much longer than other center ivory distinguish it from mammoth
mammal ivories, most bones, veg- Labret ivory, which has acute arc angles.
etable ivory and shells. Hence, a long Turkana peoples, Kenya None of the other mammal ivories
uninterrupted section may be indica- Mid-20th century have the pattern, nor does bone, veg-
tive of elephant ivory. Similarly, be- Ivory and wood etable ivory, shell, ivory dust/glue
cause vegetable ivory derives from 5.0 x 5.0 x 5.0 cm (1 15/16 x 1 15/16 x 1 15/16 in.) composites or celluloid plastics (all of
palm nuts that are a maximum of National Museum of African Art, gift of which are sometimes used as ivory
5.08 cm (two inches) in diameter, Eileen Sobeck, 2004-9-2 substitutes). The pattern can be
only whole artifacts which are small viewed with the naked eye or under
in size (e.g., miniatures, snuff boxes, 3 low magnification. The absence of the
cane heads) could be fabricated from pattern, however, does not absolutely
this material. The weight of the ob- negate a material, as working/cutting
ject can also be a telling qualifier. the ivory from different angles, espe-
Ivory and bone are heavier than shell, cially tangential, may yield sections
horn, composite mixtures and plastics, that do not show the pattern.
which are all lightweight materials.
In the absence of the intersecting-
Visual examination is one of the arcs pattern, elephant ivory can be
most useful methods to identify distinguished from like materials if
ivory. While doing so, it is useful characteristic anatomical features are
to compare the object in question present. The Haversian System of
elongated holes (from blood vessels)
This plastic box— are typically visible all over the sur-
likely celluloid— face of bone (72-29-4). Although
has a striated sur- built up in carbonate layers, the sur-
face, an attempt face of shell is typically smooth and
to emulate ivory’s uniform. Vegetable ivory also exhibits
intersecting-arc a smooth, regular surface. Because
pattern. they are created synthetically, plastics

Photographs by
Stephanie Hornbeck



Photo Gallery

Elephant ivory substitutes shown on this page are described in detail on page 4.

left

Whale teeth

Photograph
courtesy Canadian
Ivory, Inc.

left

Hippopotamus
ivory

Photograph cour-
tesy Boone Trading
Company

above above

Note the elongated holes from Ivory from the tusks of an
blood vessels (the Haversian Arctic-dwelling whale, the
System), which are character- narwhal. Note the characteristic
istic of bone. spiral form.

Spoon (detail) Photograph courtesy Arctic Art
Lega peoples, Democratic
Republic of the Congo below
Bone
19.7 x 5.4 x 1.3 cm (7 3/4 x 2 1/8 x A pod of male narwhals gather
1/2 in.) at the Arctic ice edge to eat cod.
National Museum of African Art, gift
of Mrs. Edith Drucker, 72-29-4 Photograph by Paul Nicklen/
Photograph by Stephanie Hornbeck National Geographic Stock

above

Walrus ivory

Note the absence of a pulp cavity on this
cross section. Instead, the center is com-
prised of a nodular formation of dentine.

Photograph courtesy Canadian Ivory, Inc.

5

characterization is required, a tiny from savannah dwellers. Further, composed of an inorganic compo-
sample may be submitted to analytical genetic variation within a geographic nent, calcium hydroxyapatite (60%)
testing with Fourier Transform In- region indicates that ivory can be and an organic component, collagen
frared Spectroscopy (ftir). ftir is traced back to specific countries, and (40%). Once these mammals are no
an analytical method that character- even to specific areas within those longer living, the organic components
izes organic materials based on the en- countries. If enough organic material deteriorate over time.
ergy emitted by the bonds of specific remains in aged samples, it is
chemical compounds comprising possible to extract DNA data from As ivory desiccates (dries out), its
the composition of a sample when them as well. This method is now susceptibility to fluctuations in humid-
submitted to infrared radiation. ftir used for sourcing ivory confiscated ity increases. Low humidity levels
can immediately differentiate ivory from illegal trade, enabling (below 35%) can result in separation
from its imitators, with the exception surveillance of specific geographic or delamination (79-16-47) of the
of bone, which is very similar in regions which are the source of layers of dentine, visible in cross sec-
chemical composition. poaching. tion as a cone-within-a-cone pattern.
Checks (79-16-47) and cracks occur
dna analysis has emerged as a Characteristics of in longitudinal (96-30-1) and trans-
precise method of identification and Ivory Deterioration verse planes (2005-6-3) in locations
geographic sourcing. The method related to gaps in formation. Radial
utilizes a small sample of ivory from T he deterioration of ivory is cracks form the way wood splits
which mitochondrial and microsatel- directly related to its compo- along the grain. In combination, di-
lite dna can be isolated for compari- sition and formation. Unlike rectional cracking patterns can cause
son against data sets. This analytical the teeth of living mammals, the the ivory to exfoliate in curved rec-
method can differentiate between dentine layers of tusks are produced tangles (79-16-47).
African and Asian elephants and annually (somewhat similar to tree
within a species can distinguish forest growth in concentric layers). Like Ivory is a porous material and
living bone and dental tissues, tusks are while it can be stained intentionally

Directional cracking can Checks in longitudinal plane Cracks in longitudinal plane Cracks in transverse (cross
eventually yield delamination section) plane
of ivory layers. Tusk (detail) Tusk (detail)
Yoruba peoples, Nigeria Benin kingdom court style, Figure (detail)
(see object id and credit for object 19th century Edo peoples, Nigeria Benin kingdom court style,
79-16-47 at right) Ivory c. 1850 Edo peoples, Nigeria
130 x 12.2 x 10.4 cm Ivory Early 19th century
Photographs by Stephanie Hornbeck (51 3/16 x 4 13/16 x 4 1/8 in.) 189 x 12.1 cm (74 1/2 x 4 3/4 in.) Ivory
National Museum of African Art, National Museum of African Art, 37 x 9.4 x 10.3 cm (14 1/2 x 3 3/4 x 4 in.)
bequest of Samuel Rubin, 79-16-47 purchased with funds provided by the National Museum of African Art, gift
Smithsonian Collections Acquisition of Walt Disney World Co., a subsidiary
Program, 96-30-1 of The Walt Disney Company, 2005-6-3

6

Elephants in Amboseli National Park Regulations

West of Namanga, Kenya Since the 1970s, the international trade of elephant ivory has been
highly regulated by a number of acts and laws; these apply to the
Photograph by Eliot Elisofon, 1959 importation and travel of artifacts across international borders.
Sometimes the laws overlap, in which case the stricter law applies.
eepa eecl 24721, Eliot Elisofon Photographic
The Lacey Act (1900 and Convention on Interna-
Archives, National Museum of African Art
later amendments)—prohibits tional Trade in Endangered
with colorants, it can also be stained trade of wildlife taken in violation of
any state or foreign wildlife law or reg- Species of Wild Fauna and
by the dirts and oils associated with ulation; affects interstate commerce.
Flora (cites)—an agreement, first
handling. The Endangered Species Act instituted in 1975, among 173 nations
to eliminate illegal trade in animals
As ivory desiccates it loses its (1973)—designed to prevent the ex- and plants, their parts, and associated
tinction of native and foreign species products. Although legally binding on
surface luster and becomes harder. of wild fauna and flora; lists Asian ele- the parties (countries that have volun-
phants as “endangered” (in danger of tarily agreed to be bound by the con-
With the passage of time, these extinction) and African elephants as vention), cites regulations do not take
“threatened” (in danger of becoming the place of national laws. The cites
changes can make visual identifica- endangered). This act prohibits ele- Ivory Control System focuses on the
phant parts and products from being ivory trade.
tion more difficult. Indeed, ancient imported into the United States except
under certain conditions. Artifacts The African Elephant Con-
ivory, bone and wood (as from carved of elephant ivory may travel
legally if accompanied by documenta- servation Act (1988)—prohibits
archaeological contexts) can appear tion proving that their provenance the import of raw or worked ivory into
pre-dates this act. the U.S. with certain exceptions. This
quite similar, requiring the use of act also established a grant program
to fund elephant conservation efforts.
analytical testing for identification
To be fully compliant with the laws and regulations on elephant ivory, it is
(see Identification of Ivory). im-portant to have documentation providing dates of ownership and
provenance. Only ivory artifacts that are older than 100 years, were
Laws & Regulations acquired before 1977 and have documentation to prove it, may travel
legally over international borders. U.S. regulations are more restrictive,
T he populations of both banning imports except for scientific and enforcement specimens,
African and Asian elephants household effects, musical instruments, and traveling exhibitions. Ivory
(and ivory composite) artifacts must be accompanied by a CITES Permit or
have declined dramatically Pre-Convention Certificate for initial acquisition and whenever they cross
since the mid-20th century. Accord- borders. Lack of compliance may result in artifact confiscation and criminal
ing to the United States Fish and penalties.
Wildlife Service (which regulates and
enforces compliance with national The National Museum of African Art is fully compliant with the national
and international importation laws and international laws that apply to artifacts made of elephant ivory.
that apply to fauna and flora) and the
National Zoo, while habit destruction 7
and fragmentation increasingly
threaten elephant populations, the
greatest threat to African Elephants is
poaching (illegal killing) to supply
the highly lucrative ivory market. In
the 1980s their population declined
alarmingly from 1.5 million to
600,000 in just one decade, and
recent estimates approximate that
35,000 elephants have been illegally
killed each year.

In Africa and Asia, the fates of art market was achieved in July In 1999, cites members eased the
elephants are affected for good or ill ivory trade embargo by allowing
by human activity. In some regions 2008, when eBay announced that it
with effective wildlife conservation South Africa, Namibia, Botswana
methods in place, their populations was suspending trade of ivory
have been stable or increasing but, and Zimbabwe to sell government-
most countries are showing (except for small quantities, such as owned stockpiles amassed before
population declines. 1989 to Japan, and in 2007 CITES
decorative inlays). allowed China and Japan to import
Botswana now has the largest 106 tons of ivory from new stockpiles
elephant population, and some of its Embargoes held in these four African countries.
neighbors (Namibia, South Africa and The proceeds were to be directed
Zimbabwe) allow trophy hunting of T he dramatic decline in ele- towards elephant conservation and
large males to raise revenue for con- phant populations from the local community benefits, and Japan
servation and community develop- poaching of the 1980s led to and China were allowed only to use
ment. Yet, poaching continues to be several International efforts. In 1989, the ivory within their domestic mar-
an enor-mous issue for regions that the U.S. imposed a moratorium on
cannot adequately oversee elephant imports. Then it led member countries kets. Despite the effort to periodically
ranges. Attempts to staunch poaching of CITES, the Convention on Inter-
and illicit trade, while addressing national Trade in Endangered Species alter market dynamics with strictly
increasing stockpiles of ivory from of Wild Fauna and Flora, to adopt a
elephants that have died of natural worldwide ban on commercial trade of controlled legal sales, major seizures of
causes, are dilemmas that have inter- ivory, recognizing that the African illegal ivory have increased since
national implications. A series of elephant was “threatened with then, with shipments as large as 6.5
collaborative efforts have resulted in extinction” due to poaching to meet tons from East and central Africa
the establishment of laws and reg- market demand. To call international seized in several Asian countries.
ulations (See Regulations sidebar). attention to the devastating effects of
the ivory trade, Kenya in 1989 burned The fates of elephant populations
An important step for the popular 12 tons of elephant tusks rather than
sell them and many countries (in- over the past 30 years bear witness to
cluding the U.S.) have subsequently
destroyed their stockpiles. the contemporary demand for ivory.

Intricately carved artifacts, billiard

A pile of ivory, valued at
$3 million, is confiscated
by Kenyan game wardens
and burnt by authorities.
Nairobi, Kenya
Photograph by Tom Stoddart
Archive, July 1989

above right
Elephants in Amboseli Female figure
National Park Yoruba peoples, Oyo or
West of Namanga, Kenya Owo region, Nigeria
Photograph by Mid-19th century
Eliot Elisofon, 1959 Ivory, black stone
eepa eecl 24732 H. 30 cm (11 7/8 in.)
Eliot Elisofon Photographic Acquisition grant from the
Archives, National Museum James Smithson Society and
of African Art museum purchase, 85-9-1

8

balls, piano keys and medicinal sub-
stances attest to the value of ivory for
multiple markets. Yet, it is incumbent
upon the individual buyer to be in-
formed about the legal aspects of
ivory acquisition. While the National
Museum of African Art’s collection
includes numerous ivory master-
pieces, all of them pre-date the 1989
ivory trade embargo. It is hoped that
the information provided here will
assist with ivory identification, promote
the responsible collection of ivory and
foster appreciation of the remarkable
animals that produce it.

left + inset detail
Tusk
Kongo peoples, Democratic Republic
of the Congo and Angola
c. 1860
Ivory
72.4 x 14.6 x 6 cm (28 1/2 x 5 3/4 x 2 3/8 in.)
National Museum of African Art,
museum purchase, 96-28-1
below
“Two Ivory Tusks—Zanzibar”
Photograph by a.c. Gomes and Company,
Zanzibar, c. 1910
Postcard, collotype
eepa Postcard Collection, Tanzania/Zanzibar
Eliot Elisofon Photographic Archives,
National Museum of African Art

9

Congo Français.
No. 281—Achats d’ivoire
à Brazzaville
(French Congo.
No. 281—Buying ivory in Brazzaville)
Photograph by Jean Audema, c. 1905
Postcard, collotype
Published by
Impriméries réunis de
Nancy, France, c. 1910
eepa Postcard Collection 1985-140043-02
Eliot Elisofon Photographic Archives,
National Museum of African Art

Selected Bibliography & Links Penniman, T.K. Pictures of Ivory and Other Nielsen, John. “dna Detectives Track Elephant
Animal Teeth, Bone, and Antler. 2nd Poachers” All Things Considered, February
Identification and printing. Oxford: Pitt Rivers Museum, 26, 2007, http://www.npr.org/templates/
Characteristics 1984. story/story.php?storyId=7599673

Bassani, Ezio and William B. Fagg. Africa and Ross, Doran H., editor. Elephant: The Animal and Saito, Kim. A Primer to Endangered Species Law:
the Renaissance: Art in Ivory. Edited its Ivory in African Culture. Los Ange- Obtaining Federal Permits for Specimens
by Susan Vogel. New York: The Center les: Fowler Museum of Cultural History, Protected by Endangered Species Laws.
for African Art, 1988. Washington, dc: Office of the Registrar,
University of California, Los Angeles, 1992. Smithsonian Institution, 1993.

bbc News, “EBay to Ban Sales of ivory Goods,” Smithsonian’s National Zoological Park. Traffic:: the wildlife trade monitoring network,
October 21, 2008, http://news.bbc.co.uk/ Asian Elephants. https:// a joint program founded in 1976 of the
2/hi/americas/7681903.stm nationalzoo.si.edu/Animals/ World Wildlife Fund (wwf) and the World
AsianElephants/factasianelephant.cfm. Conservation Union (iucn); the world’s
Bell-Leask, Jason. “The Twentieth Anniversary Accessed 3 May 2016. largest wildlife trade monitoring network;
of the Ivory Trade Ban,” October 27, 2009, operates the Elephant Trade Information
http://advocacy.britannica.com/blog/advo- Thornton, Jonathan. “The Structure of Ivory and System (etis) on behalf of cites,
cacy/2009/10/the-twentieth-anniversary- Ivory Substitutes” in aic Pre-Prints. http://www.traffic.org/home/
of-the-ivory-trade-ban Wash-ington dc: The American Institute
for Conservation of Historic and Artistic United States Fish and Wildlife Service,
cameo: Conservation & Art Material Encyclo- Works, 1981, 173-181.
pedia Online Museum of Fine Arts, www.fws.gov
Boston, http://cameo.mfa.org/ United States Fish and Wildlife Ivory Identifica-
tion Guide, www.lab.fws.gov/ivory Wasser, Samuel et al. “Assigning African
Elephant dna to Geographic Region of
Espinoza, Edgard and Mary-Jacque Mann. Laws and Regulations Origin: Applications to the Ivory Trade”
Identification Guide for Ivory and in pnas 41 (101), October 12, 2004,
Ivory Substitutes. www.fws.gov/lab/ Convention on International Trade in Endan- 14847-14852. (www.pnas.org)
ivory.phb. Accessed 1 May 2016. gered Species of Wild Fauna and Flora
(cites), www.cites.org Acknowledgments
Krzyszkowska, Olga. Ivory and Related Materials:
An Illustrated Guide. London: Institute Earth Report, Jessica Levin Martinez, educator for scholarly
of Classical Studies, 1990. http://www.tve.org/earthreport/archive/ programs, provided valuable contributions to the
doc. cfm?aid=1876 section on embargoes and the bibliography.
Milliken, Tom. 2014. Illegal Trade in Ivory Curator Bryna Freyer and conservation scientist
and Rhino Horn: An Assessment Report Fay, J. Michael. “Ivory Wars: Last Stand in Zak- Odile Madden shared helpful and illuminating
ouma.” National Geographic, March 2007 insights. Lisa Buck Vann, senior graphic designer,
to Improve Law Enforcement Under the (video), http://link.brightcove.com/ser- designed the document.
vices/link/bcpid1507785211/ Photographs by Franko Khoury unless noted
Wildlife TRAPS (Trafficking, Response, bclid1508311659 /bctid1508326013 otherwise.
Special Thanks to Marshall Jones, Senior
Assessment,and Priority Setting) International Fund for Animal Welfare, Conservation Advisor, National Zoological Park
Program. USAID, Washington D.C., and http://www.ifaw.org/ for crucial updates to this document, May 2016.
TRAFFIC International, Cambridge.
U.K. http://www.traffic.org/ Martin, Meredith. Elephant Destiny: Biography
home/2014/9/22/new-report-identifies- of an Endangered Species in Africa. New
actions-needed-to-curtail-illegal- York: PublicAffairs, 2003.
ivor.html. Accessed 3 May 2016.
10
Museum Conservation Institute, Smithsonian,
www.si.edu/mci/taking_care/ivory.html