Iran's coals occur in the Alborz and Central Iran basins. One of the important coalfields in the Alborz basin is the Lushan coalfield, the focus of our investigation. It is located at the northern mountain ranges of Iran. Our goal was to determine which factors control coal quality. The coal-bearing Shemshak Formation mainly consists of sandstone, shale, siltstone, and clay stone. Twenty four coal samples were collected and analyzed for major and some trace elements using X-ray fluoresence spectroscopy (XRF). The abundance of these elements is discussed in relation to local geological conditions. The correlation between the various elements is demonstrated through scatter diagrams and possible genetic associations are discussed. The average concentrations of some major and trace elements such as Sr, Ba, Si, Ca, Mg and Mn, are higher than those of most coals in the world, while the others fall within global ranges. (C) 2004 Elsevier B.V. All rights reserved.