Dun Mountain, Red Hills, and Red Mountain, are three of the largest ultramafic bodies associated with Permian rocks in the South Island of New Zealand. In the three intrusions a central core of relatively unserpentinized dunite, harzburgite, and pyroxene peridotite, is surrounded by a margin of serpentinite. At the western margin of the Red Hills intrusion, the Permian volcanics show high-grade thermal metamorphism with development of pyroxene hornfels at the contact.