Determining the provenance of obsidian in southern Patagonia using optical properties

FERNÁNDEZ, MARÍA VICTORIA; LEAL, PABLO

ARCHAEOMETRY

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2014 vol. 1 p. 1 - 18

0003-813X

This paper aims to evaluate the optical properties of natural glasses that might be useful to identify different sources of archaeological samples. Thus, obsidians from six localities of Patagonia were analyzed. Even though color, alteration degrees, crystaloclast composition and textures are important properties to identify sources, all these features do not always lead to a conclusion. In this regard, refractive index (ND) becomes a helpful tool because it could changes not only due to the chemical composition of natural glasses but also by their different thermal history. Measures obtained on Patagonian obsidians suggest that their ND range between 1.47 and 1.49, however the refractive index of some deposits is constrained enough to discriminate between them.