Twenty-six lignite samples were collected from the Kardia lignite field (Ptolemais, Greece). Ash content, moisture and CO2 were determined. The lignite samples were heated at 900 degrees C producing 26 ash samples. The chemical composition (major and trace elements) both of the lignite samples and ash products was determined using INAA, ICP-OES and ICP-MS. CaO, SiO2 and Al2O3 are the dominant oxides both in lignite and ash samples. A relative decrease of SiO2 and Al2O3 as well as an increase of CaO was noticed in the deeper lignite samples. Sr, Cr, Ni, V and Ba were found to be the most abundant both in lignite and ash samples. Sr displays a relative increase while Ni and Cr decrease with depth in the lignite samples. In the ash samples, Ni shows the most obvious decrease with depth. (C) 2007 Elsevier Ltd. All rights reserved.