Magnetization and electrical resistivity measurements on an iron‐rhodium alloy of approximate composition FeRh, having CsCl‐type structure, confirm recent x‐ray and neutron diffraction evidence for a first‐order antiferromagnetic‐ferromagnetic transition at about 350°K. From 350°K down to 77°K, an essentially constant, field‐independent susceptibility of about 1×10−4emu/g is observed. Above 350°K, the alloy behaves like a normal ferromagnet with a Curie point of 675°K and a saturation magnetization (extrapolated to 0°K) of 130 emu/g. This &sgr;0value is equivalent to an average atomic moment of 1.85 &mgr;B, or to 3.85 &mgr;Bper iron atom if the rhodium moment is assumed to be zero. Alternatively, if the iron moment is taken to be 2.2 &mgr;B, the rhodium moment has to be about 1.5 &mgr;B. Qualitative results are given for the effect of high magnetic fields and pressures on the first‐order transition temperature of this alloy.