“…However the XRF method is faster, cheaper and easier for mass analyses. 11 We analyzed different configurations of the XRF for determining elemental composition of organic fossils. To excite a characteristic radiation, we used ampoule sources (55Fe, l~ 147pm, 241Am, 238pu), continuous radiation of roentgen tubes with different anticathodes (Cr, Fe, Cu, Mo, Rh, Ag, W, Re), and intensive monochromatic radiation obtained by conversion of continuous radiation of power roentgen tubes on several re-emitters (Fe, Cu, Zn, Mo, Cd).…”