Susceptibility of Fe in Cu

The M\"ossbauer effect of Cu:Fe has been measured for $30 \mathrm{mK}lTl100 \mathrm{K}$ in external fields up to 60 kg. A constant temperature-independent term is subtracted from the hyperfine fields. After this correction the local susceptibility is in agreement with bulk magnetization, neutron diffraction, and NMR data. At the very lowest temperatures the local susceptibility becomes temperature independent, in agreement with theoretical expectations.