NB: The following excerpt is provided on the web site in lieu of an abstract.
Since 1981, we have investigated a great variety of sherds originally collected and dated by Fontes et al. The samples originated from Tondidarou in Mali, located in the floodplain of the interior delta of the Niger river.
While a study of these sherds was being done by Fontes et al., the authors carried out elemental composition analyses by means of the PIXE (Proton Induced X-ray Emission) technique, neutron activation, and scanning electron microscopy. As a result of these analyses, we were able to show that the temper in the clay can modify the elemental composition of the material and consequently both the characteristic ``fingerprint'' and the interpretation of the pottery analyses.
In certain cases more precise information can be obtained from the study of the nature and composition of the temper itself. Occasionally, this information can be used to identify the region in which the pottery was made. Also, one can obtain information on the potter's techniques.