Six serpentinites occur in the Moinian granulites of the north-east Ox mountains. Four have been known for some time and have been previously described. Additional information on these and the associated vermiculite deposits is provided. The remaining two serpentinites are described for the first time. A pyroxenite vein associated with one of these may have been produced by metamorphic regeneration. The relationship of some of these serpentinites to the probable position of the Highland Boundary fracture-zone in Eire is also discussed. Brief comparison is made with serpentinites occurring in the Scottish Moinian.