Spectroscopic and ancient geomagnetic field intensity studies on archaeological pottery samples, India

Abstract

Spectroscopic and paleointensity studies have been performed on archaeological pottery samples from Mayiladumparai, Tamilnadu, India. The clay mineral type and its level of structural deformation due to firing were studied from their Fourier Transform Infrared (FTIR) Spectra. The maximum firing temperature attained during baking, firing conditions (open / reduced atmospheric) and iron mineral phase changes were well established. Intensive rock magnetic properties on these samples were carried out in order to select the samples for paleointensity measurements. The results showed that all the samples were magnetically enhanced having superparamagnetic grains with Curie temperature of magnetite (580 °C) and yielded mean paleointensity value of 48.71±0.16 μT. © Lithuanian Physical Society, 2008.