Estimateof firing temperatures through bone-based chalcolithic decorated pottery

Guadiana River Chalcolithic middle basin (Badajoz, Spain) pottery was in many cases decorated with bone, which suffers a hydroxyapatite to β tri-calcium phosphate transformation while firing. The evolution of physico-chemical characteristics of bone decorations and experimentally heated fossil bone as a function of temperature through 1) major XRD planes, and 2) OH librational mode at 630 cm^–1 in the FTIR spectra let us establish a correlation between the physico-chemical features and firing temperature, allowing the estimate of firing temperatures for bone decorated pottery. What is a reliable criterion to differentiate over potters behavior and skill during the pottery production.