  While experiments on metals have been performed since the early days of NMR
(and DNP), the use of bulk metal is normally avoided. Instead, often powders
have been used in combination with low fields, so that skin depth effects could
be neglected. Another complicating factor of acquiring NMR spectra or MRI
images of bulk metal is the strong signal dependence on the orientation between
the sample and the radio frequency (RF) coil, leading to non-intuitive image
distortions and inaccurate quantification. Such factors are particularly
important for NMR and MRI of batteries and other electrochemical devices. Here,
we show results from a systematic study combining RF field calculations with
experimental MRI of $^7$Li metal to visualize skin depth effects directly and
to analyze the RF field orientation effect on MRI of bulk metal. It is shown
that a certain degree of selectivity can be achieved for particular faces of
the metal, simply based on the orientation of the sample. By combining RF field
calculations with bulk magnetic susceptibility calculations accurate NMR
spectra can be obtained from first principles. Such analyses will become
valuable in many applications involving battery systems, but also metals, in
general.
