Sixteen international and six inter‐laboratory geochemical reference samples have been analysed for their selenium content. No previous Sedata are available for thirteen of them. Selenium has been separated from silicate matrix by volatilization and was determined with flameless atomic absorption spectrometry. An outline of the procedure is given. The limit of detection is 10 ng Se per 1 g of sample. Time required for one full analysis is 1.2 to 2.5 hours depending on amount of sample to be volatilize