The line shape, amplitude as well as half‐width, to be expected experimentally from a natural linewidth thin source and a natural linewidth Mo¨ssbauer absorber has been computed as a function of the thickness of the absorber. The experimental result using stainless steel source and absorber and correcting for background has double the expected width, but nearly the correct fractional change in rate. This is compatible with a blurring due to dissimilar microenvironments of about ±0.10 mm/sec.