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Introduction to ivory identification Developed by the CITES Secretariat GreenCustoms Knowledge Series No. 12.

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Presentation on theme: "Introduction to ivory identification Developed by the CITES Secretariat GreenCustoms Knowledge Series No. 12."— Presentation transcript:

1 Introduction to ivory identification Developed by the CITES Secretariat GreenCustoms Knowledge Series No. 12

2 2 Questions to answer What is ivory? How long has ivory been used? What kinds of ivory are in trade? How to differentiate between different kinds of ivory? How to identify substitutes? How to spot counterfeit ivory?

3 3 What is ivory? The word “ivory” was traditionally applied only to the tusks of elephants However, the chemical structure of the teeth and tusks of mammals is the same regardless of the species of origin, and the trade in certain teeth and tusks other than elephant is well established and widespread Items from species other than mammals have also been called “ivory”

4 4 What is ivory? Tusks are extremely large teeth projecting beyond the lips Teeth of most mammals consist of a root, a neck and a crown, and a tusk consists of a root and the tusk proper Teeth and tusks have the same physical structures: pulp cavity, dentine, cementum and enamel

5 5 What is ivory? Tooth and tusk ivory can be carved into an almost infinite variety of shapes and objects Tusks can be carved in a way that retains their characteristic shape Warthog tusks, teeth from sperm whales, killer whales and hippos can be superficially carved, and also retain their original shapes

6 6 What is ivory? Ivory can also be found in less-recognizable form, such as inlays and small items

7 7 Ivory in trade Ivory has been valued for a long time, with the first recorded use in carving by Cro-Magnons living from about 40,000 to 10,000 years ago in the Upper Paleolithic period of the Pleistocene epoch

8 8 Ivory in trade Egypt, 2600 BC Europe, 12 th -14 th Centuries

9 9 Ivory in trade Japanese artists starting in the 17th century cleverly invented the miniature sculptures known as netsuke to serve a very practical function (kimonos did not have pockets !) Modern copies of old netsuke designs are popular as art objects, and are often made from ivory

10 10 Ivory in trade Netsuke carvings will have two small holes through which a braided silk cord was passed Genuine items and well-made copies will have holes of different sizes, as the larger hole will accommodate the knot Modern netsuke created as tourist items generally have holes of similar size, or holes that do not connect

11 11 Ivory in trade Modern use and trade –D–Decoration, art –C–Cultural objects –M–Musical instruments –N–Name seals

12 12 Ivory in trade Modern use and trade –D–Decoration, art –C–Cultural objects –M–Musical instruments –N–Name seals

13 13 Ivory in trade Modern use and trade –D–Decoration, art –C–Cultural objects –M–Musical instruments –N–Name seals

14 14 Ivory in trade Modern use and trade –D–Decoration, art –C–Cultural objects –M–Musical instruments –N–Name seals

15 15 Kinds of ivory Elephant (Asian, African) Mammoth (fossil ivory) Hippopotamus Walrus (including fossil walrus ivory) Narwhal Sperm whale Warthog Hornbill Natural substitutes –Bone –Composites –Shell –Vegetable ivory Synthetics, fake ivory –Plastics –Polyester resins –Synthetics –Casein –Celluloid

16 16 Real or fake...? It is not so straightforward, or easy to tell... Ivory identification... and in which CITES Appendix? Bone Celluloid Warthog Synthetic III Walrus II Hippo I Hornbill

17 17 Ivory identification Elephant and Mammoth –Polished cross-sections of elephant and mammoth ivory dentine display uniquely characteristic Schreger lines, commonly referred to as cross-hatchings, engine turnings, or stacked chevrons –The intersections of Schreger lines form angles, which are on average 100-115 deg. (obtuse) in Asian/African elephant ivory

18 18 Ivory identification Elephant and Mammoth –Polished cross-sections of elephant and mammoth ivory dentine display uniquely characteristic Schreger lines, commonly referred to as cross-hatchings, engine turnings, or stacked chevrons –The intersections of Schreger lines form angles, which are on average 100-115 deg. (obtuse) in Asian/African elephant ivory Mammoth Elephant

19 19 Mammoth (non-CITES)

20 20 Elephant

21 21 Mammoth (non-CITES)

22 22 Ivory identification Remember, Schreger lines appear in cross-section In a three-dimensional carving, it is usually possible to find a side that corresponds to a cross-section However, items that are cut length-wise in thin layers (such as piano keys) will not have these lines, and may exhibit wavy or parallel lines on their surface