Coarse sillimanite prisms, over 5 centimetres in length, are developed in pelitic schists on Zofka Ridge adjacent to a plutonic contact. Within these schists, sillimanite may comprise 14 to 15 per cent of the rock, with garnet accounting for another 22 to 25 per cent (Lowes, 1972). These strata are assigned to the Cretaceous and/or Tertiary Settler Schist.