As a model material of fluorite type structure, single crystals of CaF 2 were irradiated with various heavy ions (from 3 2 S to 2 0 9 Bi) of specific energies between 1 and 12 MeV u - 1 . Using a profilometer, out-of-plane swelling was measured by scanning over the border line between irradiated and virgin areas of the sample surface. The step height as a function of the ion fluence exhibits a linear increase in the initial phase and saturates at high fluences. Track radii contributing to the swelling effect are deduced. Above a critical energy loss of about 5 keV nm - 1 , the initial swelling rate per incident ion shows two separated regimes. Finally, the response of CaF 2 submitted to high electronic energy loss is discussed in combination with earlier track observations by transmission electron microscopy.