INTRODUCTION
A decade ago, Brodie and Renfrew (Reference Brodie and Renfrew2005) called for adequate actions in the protection of the world’s cultural heritage from looting. This call is now even more urgent and has to be extended to scientific communities. The looting of the archaeological and ethnographic heritage from emerging countries and war zones as documented by archaeologists (e.g. Parcak et al. Reference Parcak, Gathings, Childs, Mumford and Cline2016) is also a subject regularly mentioned in the media, often in connection with the role looted antiquities might have in supporting terrorism and war. However, looting of cultural heritage is a worldwide phenomenon, which increases in areas of war and social unrest or natural catastrophe. For decades, calls for the introduction of new legislations to protect the world heritage were made by archaeologists (Kersel Reference Kersel2006). Often such measures were disputed and criticized by antiquity dealers and collectors who argue that the legal trade in antiquities is suffering due to such measures and that it is the protection of endangered sites and museums that is needed. However, considering the complicated political and social situation regarding the sites in question, this might be impossible for the time being; therefore, action is needed at the end of the chain or in transit states.
It can be argued that the intensification of looting is directly linked to the significant commercial value reached by certain archaeological objects on the market. Recent “record sales” at public auctionsFootnote 1 contribute to the rise in illegal excavation (digging) activities and museum thefts, as well as the creation of illicit export outlets. Yet, before committing to major financial expenditures, the buyer will, most of the time, request a proof of authenticity. Obviously, forgeries or recent copies have little value on the art market. While the provenance of some objects may refer to a collection assembled prior to recent falsifications,Footnote 2 it is generally only scientific proof, i.e., thermoluminescence (TL) or radiocarbon dating that will reassure the buyer. Therefore, absolute dating of archaeological and ethnographic objects circulating on the art market has become an integral part of the mechanism of speculation, with the necessary corollary of a potentially high increase in the resources of terrorist movements.
ROLE OF TL DATING IN THE DEVELOPMENT OF THE ILLICIT TRADE IN AFRICAN ART
As an example foreshadowing the current role of AMS dating at the center of the present discussion, we summarize here the history of the use of absolute dating by TL in the field of African art, and the role this process has played in the explosion in the looting of archaeological sites (Huysecom Reference Huysecom2011).
The idea of providing absolute dating for archaeological objects proposed for sale was born in the context of a craze for African terra cotta sculptures. This trend followed the 1977 discovery of a very beautiful sculpture representing a recumbent figure, which was made during scientific, i.e. legal and authorized, excavations at the Malian tell of Djenné-Jeno, a UNESCO World Heritage Site dated by 14C and estimated to be occupied between 250 BC and AD 1400 (McIntosh and McIntosh Reference McIntosh and McIntosh1980). Speculators in “primitive arts” were immediately interested in this discovery, published in the journal African Arts (McIntosh and McIntosh Reference McIntosh and McIntosh1979).Footnote 3 In 1980, the young Belgian Bernard de Grunne wrote and published a Master’s thesis at the University of Louvain-la-Neuve about the collection that his father, Count Baudouin de Grunne, had just assembled, inspired by the Djenné-Jeno discovery (de Grunne Reference de Grunne1980). In this work, most of the pieces were dated using the TL method at the University of Oxford laboratory.
Within a few years only, a new market was created:Footnote 4 in 1982, the price of Malian terra cotta sculptures, until then nearly nonexistent in the art trade, rose by a factor often higher than 1000. The speculation and demand that followed caused many forgeries to be created. The TL analyses of the Oxford laboratory were thus systematically requested by the large auction houses and art dealers, with a resulting explosion in the value of dated archaeological pieces to the detriment of those on sale without absolute dating.
A direct consequence of soaring prices was the acceleration of illegal digging on archaeological sites. In 1993, the Valleys of the Niger exhibition in Paris, Leiden, and several West African capitals revealed the magnitude of the destruction of archaeological sites by looters. It is estimated that in the Inland Niger Delta and Mali, 80–90% of the archaeological sites have been affected by such plundering (Dembele et al. Reference Dembele, Schmidt and van der Waals1993; personal observation during field missions from 1988 to 2010).Footnote 5 During this period, a documentary film (van Beek and Evans Reference Van Beek and Evans1991) and a conference resulting in an important publication strongly condemned this disturbing situation (Schmidt and McIntosh Reference Schmidt and McIntosh1996).
The voice of professional archaeologists was taken seriously and, after several resolutions, positions taken and pressure made by the councils of different international associations [the International Union of Prehistoric and Protohistoric Sciences (UISPP), the Society of Africanist Archaeologists (SAFA), and the Pan-African Association for Prehistory and Related Studies (PANAF)], the University of Oxford put an end in 1993 to the practice of TL dating of objects on the art market despite their non-negligible contribution.
After that, it only took a few years for private TL dating laboratories to open and provide their services to art dealers and collectors. It must be concluded today that the only benefit obtained by the scientific community is the retraction of the academic nature of TL dating used for the art market. The number of private laboratories has increasedFootnote 6 and some of them continue to produce TL dates on terra cotta cultural goods, which still provides an opportunity to date objects that are the product of looting and illicit trade.
USE OF AMS DATING TO INCREASE THE VALUE OF CULTURAL HERITAGE
Until recently, only TL dating had been used in the art trade, since 14C dating of organic materials (wood, bone, ivory, and textiles) was too destructive for objects of significant commercial value. The farily recent development of dating by accelerator mass spectrometry (AMS), requiring only a few milligrams of material, completely changes the game. During the last 2 decades, archaeological and ethnographic objects made of organic materials have been regularly dated to be studied, authenticated, and sometimes to increase their value at auction or for public and private museums.Footnote 7 For example, an ancient ethnographic statue of Malian heritage, sold in 2009 by Sotheby’s, reached a hammer price of 43,340.00 €, which was in large part due to the fact that this piece was sold with a certificate of authenticity including an AMS date by the ETH laboratory (Sotheby’s e-catalogue 2009). Even if this sale might be considered legal (the statute of limitation had likely expired since the illegal smuggling of the piece out of Mali, when it first became independent), this valorization is nevertheless ethically questionable. It should be noted that the ETH laboratory did not receive any information on the origin of this object and only a numbered sample had been provided for the dating.
Escalation in the use of this method in recent years can be clearly observed, evidenced by the systematic dating of wooden statues for the Dogon exhibition at the Musée du Quai Branly from April to July 2011 (e.g. Figures 17 and 18 in Leloup Reference Leloup2011). The dating was requested by the commissioner of the exhibition, who had personally collected many cultural goods in Mali beginning in 1952. The campaign of systematic dating of archaeological objects, without pedigree because they were acquired directly in the field and then submitted to laboratories, provided the age of these wooden sculptures, which in turn increased their value in view of their potential sale after the exhibition.
After the intensification of archaeological looting and the increase in the illicit trade of cultural goods, many archaeologists and ethnologists became concerned about the future of cultural heritage, particularly African heritage. As a result, an international round-table entitled “African Memory in Danger” was organized in September 2011 in Geneva (Mayor et al. Reference Mayor, Négri and Huysecom2015) during which ethical and deontological questions linked to 14C dating were raised for the first time (Huysecom Reference Huysecom2015). Archaeologists then assessed the impact of AMS dating on the escalation in the looting of artifacts made of organic materials and the following resolution was voted at the University of Toronto on 23 June 2012 by the participants of the 13th International Congress of the Society of Africanist Archaeologists (SAFA):
“En vue de limiter le pillage et de préserver le patrimoine culturel africain, la SAFA demande instamment aux laboratoires de datation par la méthode C14 de ne plus pratiquer de datations, pour des raisons éthiques, sur des objets (ou échantillons provenant d’objets) archéologiques, ou ethnographiques d’importance historique, pour le compte de marchands, de salles de ventes ou de particuliers.”
“With a view to limiting the looting and in order to conserve the African cultural heritage, the SAFA urgently requests, for ethical reasons, that 14C dating laboratories no longer run dating for dealers, auctioneers or individuals on archaeological material or on ethnographic items of historical significance, or on samples taken on such materials.”
The first discussion with those responsible for AMS dating at the ETH laboratory in Zurich revealed an urgent need for an involvement and an exchange of information on this issue with 14C laboratories. This is needed to raise awareness to the problem and to find appropriate solutions. The main difficulty is that several academic laboratories, which provide AMS dating, are often subcontracted to third-party laboratories. The latter usually provide a sample material with no data on provenance other than a sample identification number. Yet the client receives the date obtained with the identification code of the academic laboratory, which might be prominently displayed during the sale of the dated object. While solutions to this problem are being considered and will be found, another obstacle might soon arise. New instrumentation for AMS dating—compact AMS technology—will soon be more readily available to all laboratories, including private ones, that are specialized in increasing the value of heritage for antique dealers and collectors. The current context for the AMS dating of art objects made of organic materials thus shows clear parallels with the context two to three decades ago of TL dating of art objects made of terra cotta.
CONCLUSION
Today, we need more than simple resolutions by organizations grouping archaeologists and ethnologists from one continent or another. It has become necessary to rapidly establish an ethics standard for laboratories under which they may provide 14C dates. Such a standard could be regarded as a quality measure for all laboratories involved. The following key points should be considered:
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∙ Pre-review of the description of the object (country of origin, picture, known provenance);
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∙ The dating of archaeological and ethnological objects from emerging countries and conflict zones would require a legally binding declaration of origin, to be produced by the collectors, dealers, and auction houses;
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∙ For any object, a written statement would be required that export from any country and the import into any country has been in full compliance with the laws of each such jurisdiction;
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∙ In particular, the declaration shall state that the object has come into possession by not violating the November 1970 UNESCO Convention on the means of prohibiting and preventing the illicit import, export, and transfer of ownership of cultural property;
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∙ A requirement for any dating should be the submission of an identification form following the model of the Object ID as proposed in 1993 by the Getty Trust; this Object ID is being promoted by major law enforcement agencies including Interpol and UNESCO (see http://archives.icom.museum/objectid/about.html).
In general, the situation is critical. Areas of conflict zones are expanding, looting is intensifying, and at the same time speculation in the art trade is flourishing. Under such circumstances, entire chapters of the history of countries concerned may be threatened. Given this disturbing situation, we propose the setting up, as quickly as possible, of a working group that will contact the AMS 14C community, art dealers, and auction houses in order to launch a concerted action to establish such ethics standards. It is our strong desire to impede 14C dating of illicit objects in the future and to request that the community act for the preservation as far as possible of our unique cultural heritage and its national implementing legislations.
