L’obsidienne, or noir de la Préhistoire

International audienc

The fission-trackanalysis: An alternative technique for provenance studies of prehistoric obsidian artefacts

Agence de Developpement Economique du Doubs;Region de Franche-Comte;Societe Francaise de Chimie;Universite de Franche-Comt;Ville de BesanconProceedings of the 1998 19th International Conference on Nuclear Tracks in Solids (ICNTSs) --31 August 1998 through 4 September 1998 -- Besancon --Comparison of fission-track parameters - age and track densities - is an alternative tool for correlating obsidian artefacts with their potential natural sources. This method was applied by different fission-track groups in various regions and results were compared with those obtained using the more popular provenance identification techniques based on chemical composition studies. Hundreds of analyses prove that fission-track dating is a complementary technique which turns out to be very useful, specially when the chemical composition does not fully discriminate different sources. Archaeologically significant results were obtained applying the fission-track analysis in various regions of earth. © 1999 Elsevier Science Ltd. All rights reserved

Fission track dating and provenience of archaeological obsidian artefacts in Colombia and Ecuador

International audienceWe dated by the fission track method eighteen samples of obsidian glass. Of these, seventeen were artefacts collected in prehispanic archaeological sites from Ecuador and Colombia and one comes from a secondary obsidian source located in southern Colombia. When our data are compared to (i) the fission track ages of obsidian from volcanic sources and (ii) the PIXE chemical composition of the same artefacts and of samples from obsidian sources, eight discrete age/composition groups appear.Fifteen artefacts might come from a single unknown source: three others from sources in the Sierra de Guamani (East of Quito): one from the Mullumica rhyolitic flow and two from the Quiscatola/Yanaurcu sources. A fourth artefact migh come from the South Colombia source of Rio Hondo. At least five other sources are necessary to account for thr variety of ages and compositions found in the arefact collection studied

XRF obsidian analysis from Ayacucho Basin in Huamanga province, south‐eastern Peru*

Obsidian was broadly used along the Andean Cordillera in South America. Particularly in Peru, its use can be traced to the earliest human occupations, continuously through pre-Columbian times to contemporary Andean agro-pastoralist societies. In order to distinguish the provenance of obsidians from Peru, this paper reports a new X-ray fluorescence (XRF) analysis on several obsidians obtained in surface collections of the Ayacucho region. The analysis and source determination were made by XRF on 52 specimens. The source assignments involved comparisons between the compositional data for the specimens and the University of Missouri Research Reactor (MURR) XRF obsidian database for sources in Peru. After analysing the samples, obsidian sources were recognized and documented. All had small nodules not larger than about 4 cm. They were recovered from Ñahuinpuquio and Marcahuilca hill which belonged to the previously identified Puzolana source. Another identified source was the well-known Quispisisa, located 120 km south of the city of Ayacucho, and distributed through a vast region in central Peru. The results expand previous observations made on the obsidian provenance at Ayacucho Basin, as well as the extension of the Puzolana source between Yanama and Huarpa hills, south of Ayacucho city