Evolution of olivine and pyroxene pellets due to ion and laser irradiation. Pellets irradiated with hydrogen (H⁺) are photocomposites of the fresh surface in the left part and the 10¹⁸ ions cm⁻² irradiation in the right part. Pellets irradiated with helium (He⁺) and argon (Ar⁺) display the surface after 10¹⁷ ions cm⁻² irradiation; only the outermost annulus represents the fresh surface and was created by using a mask during irradiation. Yellow squares (3 × 3 mm in size) in the photograph of a pyroxene pellet irradiated by laser indicate the regions of the least dense irradiation that are notvisible by eye. The yellow numbers in the figure represent the spacing between two consecutive laser shots; for equivalent values of energy densities, see Table 1: the sequence of the distances relevant to one material in this figure (from left to right) corresponds exactly to the list in the table.