Very rare before 1982 at MSH, villiaumite has been found more frequently in sodalite xenoliths in nepheline syenite. Color ranges from pale orange-red to very deep carmine red. Luster is vitreous on clevages, and vitreous to waxy on faces. Diaphaneity is transparent with inclusions. Crystal Habits include fillings or partial fillings up to 10cm in size, very rarely as sharp cubic or octahedral crystals up to 10mm.
Fracture is conchoidal.
Streak is white. Associated Minerals include amphiboles, calcite, eudialyte, fluorite, nepheline, pectolite and numerous other minerals from sodalite xenolith environments.