A rather homogeneous alloy made of immiscible Fe and Cu was synthesized by using colloidal solutions, The starting materials were a mixture of 30% and 70% of iron(II) (Fe(AOT)(2)) and copper(II) (Cu(AOT)(2)) bis(2-ethylhexyl)sulfosuccinate, respectively. The nanosized alloys are fairly polydispersed, with sizes ranging from 5 to 15 nm. Varying the ratio of Fe(AOT)(2) to Cu(AOT)(2) induces very marked changes in morphology. The samples were characterized by transmission electron microscopy, X-ray and electron diffraction, Fe-57 Mossbauer spectroscopy, energy dispersive spectrometry, electron energy loss spectrometry, and room-temperature magnetization measurements.