A lead selenide mineral, tentatively identified as clausthalite (PbSe) based on optical microscopy, scanning electron microscopy with energy-dispersive X-ray (EDAX), electron microprobe, and scanning proton microprobe (SPM), has been described in a number of coals. While clausthalite has been mentioned as a possible source of Se in coal, it is present in such small quantities and sizes, that the mineral identification has not been absolutely confirmed. The mineral specimens examined in this study would contribute, not only to the Pb and Se concentrations in the coal, but also, in at least one case, to Hg concentrations. (C) 2003 Elsevier Science B.V All rights reserved.