my prediction would be that this attempt will not be successful, because the (111) planes are polar (charged), resulting in high surface energy. In some oxides this is said to induce electronic reconstruction. Here, I would expect that high quality (111) surfaces will not form.
as mentioned by K.F., the (111) surfaces of transition metal monoxides with NaCl structure are either terminated by O2- or TM2+. Therefore, the (111) surfaces of these compounds form facets with non-polar (110) planes resulting in arrays of three-sided pyramids. To get an idea about the morphology, see e.g. Fig. 5 in
Article Morphology of MgO(111) surfaces: Artifacts associated with t...