Dun Mountain–Maitai terrane

Prehistorically this ophiolite was quarried by Māori for both metasomatized argillite and pounamu (jade) which was used in the production of tools and jewellery.

In the 20th century, serpentinite was mined for fertiliser and the ophiolite remains one of New Zealand's main sources of pounamu (jade), but all other mineral exploration has failed to find economic deposits.

[4] The Dun Mountain ophiolite belt is a locally intact approximately 12 kilometres (7.5 mi) section through oceanic crust.

[7]: 230  However it is only exposed at one place in the North Island being the Wairere serpentinite quarry 190 km (120 mi) south of Auckland.

[7]: 231  Lithic clasts from the underlying Dun Mountain-Maitai terrane have been erupted from volcanoes in the Auckland volcanic field.

Maitai Group sediments folded into an isoclinal syncline
Vegetation change from the Dun Mountain ophiolite belt ultramafic rock (left) to mafic and sedimentary rock on the right. [ 5 ]