  We present a 57Fe M\"ossbauer spectroscopy study of the two incommensurate
magnetic phases in the multiferroic material FeVO4. We devise lineshapes
appropriate for planar elliptical and collinear modulated magnetic structures
and show that they reproduce very well the M\"ossbauer spectra in FeVO4, in
full qualitative agreement with a previous neutron diffraction study.
Quantitatively, our spectra provide precise determinations of the
characteristics of the elliptical and modulated structures which are in good
agreement with the neutron diffraction results. We find that the hyperfine
field elliptical modulation persists as T goes to 0, which we attribute to an
anisotropy of the hyperfine interaction since a moment modulation is forbidden
at T=0 for a spin only ion like Fe3+.
