From there, we take open skiffs down a tributary of the Xingu River.
(c) XRF spectra of the analyzed samples: the intensity scale was modified in order to observe the variation of the minor elements; the color codes are the same as for Figure 6 a.
In ancient times, sources of clays were widely available, between them soils or surface sediments have been the proper sources for ceramics without further treatment, due to their natural mixture of plastic and nonplastic components .
Ceramics is an inorganic nonmetallic material obtained through thermal processing of natural raw materials at relatively high temperature .
Two interlocking assumptions about the Amazon have persisted to this day.
The first is that the Amazon is a place of virgin wilderness, untouched by human cultivation or management; the second is that the people of the Amazon have always been — as they were found to be by twentieth-century anthropologists — small bands living by gathering, hunting, fishing, and slash-and-burn agriculture.