Two methods were used to analyse fly ash for trace elements using laser ablation inductively coupled plasma-mass spectrometry. Individual particles in polished blocks proved difficult to analyse because of the fine grain size of the particles. Identification of particles was one problem and another was loss of sensitivity for key trace elements with a very small diameter (10 mum) laser beam. Analysis using transects covering many particles mounted on slides proved more successful. Statistical analysis of the data using major elements to measure the variation in key components in the ash showed: (1) that the glass is an important location for V, Cr, Cu and Zn; (2) Cr and V are thought to be concentrated in magnetite, although the major source in the ash is the glass; and (3) As, U, Pb, TI, Mo, Se and probably Ge and Ga to a lesser extent, have a major association with the surfaces of the ash particles. (C) 2004 Elsevier Ltd. All rights reserved.