Provenience sources

Mosandl [313, 314] has found 8 C-values from -33.6 to -34.9%c for 2,5-dimethyl-4-methoxy-2H-furan-3-one ( mesifuran ) and -23.7 to -26.8%c for 2,5-dimethyl-4-hydroxy-2H-furan-3-one ( furaneol ) from strawberries. This difference, even found in products from the same source, suggests independent biosyntheses. Another natural sample of mesifuran showed a very positive 8 C-value (-18.5%c), which indicates its origin from a CAM-plant (pineapple). However, the recent data by Preston et al. [207] show that furaneol from this provenience can, but must not have quite positive 8 C-values. This and the seeming coincidence of the data for natural and nature-identical mesifurane show that the situation with these compounds is still not quite clear. 

An ideal provenience study would involve a natural material, the composition of which remains unaltered after extraction, only a small number of possible sources, an adequate number of samples from each source to adequately assess their compositional variation, and one or more combinations of elements or compounds that adequately distinguish the sources. Just as there is no proverbial spherical cow, such ideal materials are almost as rare. 

To attempt to sort out some of these issues with sourcing native copper, Ron Hancock and colleagues at the SLOWPOKE nuclear reactor facility at the University of Toronto decided to use the multielement capability of neutron-activation analysis. They started with 43 samples from 19 collections of native copper and 23 samples of copper from archaeological contexts but which were believed to be reworked metal of European origin. Eive other samples of copper from artifacts from known contexts but of unknown source were also included. To maximize the possibility that the provenience postulate would be true, they included 27 elements in their analytical procedure and got useful data for 22 of them. They also analyzed 14 subsamples from the same specimen to assess within sample variation and three modem copper samples for comparison. 

The authors of the study did not so much attempt to determine the composition of exotic pottery from different places for comparison in their study, but rather relied on the provenience postulate. The provenience postulate states that chemical differences within a single source of material must be less than the differences between two or more sources of the material, if they are to be distinguished. Thus, Mainfort and colleagues in this study argue that chemical differences within the pottery from Pinson Mounds are large, and thus all of the pottery studied in then-sample was produced locally. They found no chemical evidence for the long-distance importation of pottery. 

Provenience postulate States that if differences within a source of material are less than dif-... 

Because of the desire to trace archaeological copper and copper-based alloys back to their copper ore sources, a substantial amount of research has been done on the behavior of trace elements in native copper and in the metal during the copper smelting process, using NAA. This topic is however more appropriately considered under the Provenience section below. 

The Provenience Pcstulate has already been mentioned in the Introduction, whereby it was suggested that samples taken from either a natural source of materials, or artifacts macte from material of a given source, tended to resemble each other in... 

Craddock, in a comprehensive paper on medieval and west African bronze analysis, has clearly pointed out the inherent dangers of interpretation of analytical data for copper or copper-based alloys in terms of provenience. Provenancing metal from its composition has always proved immensely difficult even for the ancient Near East and Europe where one can normally assume that the metal has been mined, smelted, fabricated, used and discarded within the same society. In the case of West Africa where the bulk of the metal came from a wide variety of undifferentiated sources which were far distant and technically superior, the task of interpreting the metal analyses becomes all the more fraught with difficulty. In copper provenancing studies generally three assumptions have to be made ... 

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