Before the arrival of Europeans, Māori used stone to build paths and walls, but their buildings were made of wood and other plant materials.
Most of the 19th-century colonists came from Britain, where stone and brick were traditionally used for building. Because timber was readily available in most parts of New Zealand, their earliest houses were mainly of wood. Only in areas like central Otago where wood was scarce was stone widely used for cottages and houses.
As the years passed only a relatively small number of stone buildings were constructed – mainly churches, banks, public buildings, and houses of the well-to-do in Auckland, Christchurch and Dunedin. Building in stone was expensive, few stonemasons were available, and experience showed that stone buildings were badly damaged in earthquakes. Although the design of larger buildings until the 1950s was invariably based on European stone buildings, New Zealanders discovered that it was usually cheaper and easier to build in concrete, brick and wood.
Most of the 19th-century stone buildings were in areas where stone was available nearby – for example, the volcanic rocks of the western Bay of Islands, Auckland, New Plymouth, Christchurch, Timaru and Dunedin. There was limestone in Ōamaru, and schist in central Otago. Many of the early buildings were of rubble construction, where roughly shaped blocks were fitted together, and the gaps filled with mortar.
After 1910 many of the smaller, local quarries closed in favour of large quarries that were worked on an industrial scale, and often stone was transported over long distances by rail or by sea. Volcanic rocks were less used, being replaced by Coromandel granite, Tākaka marble, Bluff norite, Putaruru ignimbrite, and Ōamaru limestone. From this time onwards almost no buildings were entirely constructed in stone, but it was used for frontages, base courses, pillars, facings around windows and doors, and ornamental panels. Stone has also been used for a number of bridges as well as the seawalls around harbours in the main centres.
The only New Zealand stone being worked on a large scale in the early 2000s is Hinuera ignimbrite and Ōamaru limestone, both soft enough to be sawed into blocks and panels.
Chips and pebbles of many other rock types are set in concrete and made into panels for exterior cladding. Stone from local quarries is used for paving, fireplaces and chimneys, walls and a variety of decorative work. Sheets of imported stone are also used for cladding in many commercial buildings.
Splitting and trimming rock is a traditional form of prison labour. Most of the kerbing stones used on streets in the central part of Auckland were produced by prisoners held in Mt Eden jail.
Working as a stonemason has never been a popular trade in New Zealand. In the 19th and 20th centuries the work was heavy and dirty, eye injuries were common, and employment depended on the relatively small number of stone buildings constructed. As a consequence, most stonemasons were multi-skilled, and also worked as builders. A number of Dalmatians emigrated to the Auckland area to work as stonemasons in the 1920s. Also at that time, stone workers from northern Italy began migrating to Auckland, where they dominated the manufacture of terrazzo (flooring of marble or stone chips) for several decades.
In recent years there has been an increase in the popularity of stone walls in the Auckland area, mostly built by groups of Polynesian stonemasons.
Skills as a stonemason have traditionally been learnt on the job or passed down through a small number of families. Otago Polytechnic offers a one-year course in stonemasonry.
Over the years many New Zealand stones have been used in buildings, but few have proved both durable and economic to work. Several qualities are needed:
All rocks can be grouped into three major categories:
The technical nomenclature of rocks is complex, and is confused by the fact that most of the common building stones in New Zealand have been given trade names. These combine the quarry location and a generalised rock name that is not always accurate or helpful – for example Coromandel granite (which is diorite rather than granite), Ōamaru stone (limestone), and Hinuera stone (ignimbrite). Overseas building stones are often named for their appearance, such as Red Dragon and Blue Pearl.
Mountain ranges of greywacke form the backbone of New Zealand, and it is the most abundant rock type in the country. But it is difficult to use as a building stone because the more massive rocks do not split naturally, and in other places it is too fractured. River-worn boulders have been used for building stone walls in some places, and a small number of churches and other buildings have been made of greywacke.
Limestone is a rock composed mainly of lime (calcium carbonate – CaCO3), almost always formed from shelly material. Some limestones are very fine-grained, originally being a limey ooze on the sea floor, but in other rocks large shell fragments can be seen. Limestone is widespread in New Zealand, and formed mainly in late Eocene to Oligocene time, 25–40 million years ago when much of the New Zealand region was submerged beneath the sea.
The hardness of limestone depends on how deeply it has been buried. Softer rocks such as Ōamaru stone have been compacted, but can still be carved and cut with a saw. Most other limestones have been more deeply buried. The calcium carbonate has crystallised in the pore spaces to form a hard, dense rock that can be polished. When limestone is deeply buried and heated it recrystallises so that the original shelly material cannot be recognised, and it is then called marble.
New Zealand’s most important building stone is a very pure, massive limestone, soft enough to be readily sawn and worked. It is composed mainly of microscopic bryozoa that accumulated as a submarine shellbank in the Ōamaru area. Because of its purity, it is mainly white. Small amounts of volcanic ash give the lower part a yellow tinge, and result in a poorer quality stone.
With pride in its heritage of neoclassical buildings, Ōamaru has adopted the name Whitestone City for promotional purposes, and holds an annual heritage week in November. Historian Erik Olssen regarded the main street of Ōamaru as a political statement: ‘Ōamaru’s leaders celebrated, in glossy white limestone, the triumph of the pioneers and the certainty of progress through capitalism.’ 1
Quarrying began about 1860, and Ōamaru stone was obtained from many different quarries inland and south of Ōamaru. Virtually all stone used for building since the 1940s has come from Taylors or Parkside quarries at Weston, and the latter still works the purest limestone. To extract the stone, it is cut into 2-tonne blocks by a chainsaw cutter, and broken out with a fork-lift loader. In an adjacent factory these blocks are cut into slabs by large circular saws.
The ease of dressing Ōamaru stone made it popular for buildings throughout New Zealand. It has been widely used for decorative work around windows and doors, as well as carved pillars and gargoyles. After several decades it tends to weather and flake. Many older buildings have needed cleaning and repair, but this can now be largely avoided if the stone is sealed.
Most limestones are harder than Ōamaru stone, and are much more difficult to work. They have, therefore, been mainly used for decorative facing stone. Although the term marble is often used for such rocks, the original shells are still visible, and they are technically limestone.
Whāngārei marble is the commercial name for pale-coloured limestone quarried near Whāngārei and widely used for facing stone. It takes a high polish, and has been used for decorative facing panels in several buildings. Similarly, Hanmer marble is the commercial name for a dense limestone with a pinkish-brown colour found in the Waiau valley, north Canterbury. The distinctive colour is due to the presence of small amounts of volcanic ash.
Different quarries sometimes give their own names to the rock they produce, even if it is similar to rock produced nearby. Tākaka marble has also been called Nelson marble and Caanan marble. All these names are from the same area of marble that geologists call Mt Arthur marble.
Tākaka marble is a true marble that occurs in the area around Tākaka, and has been worked from a number of quarries on Tākaka hill or in the nearby Holyoake valley since the early 1900s. Impurities vary from place to place, so each quarry produces distinctive coloured marble, ranging from white to pink or grey, and locally almost black.
The new Kairuru quarry, in the Holyoake valley, was the main producer in 2005 – mainly building panels and tiles. The rock is a coarse, crystalline marble with orange veins and irregular staining. The old Kairuru quarry, a little further down the hill, produced the grey marble used in Wellington’s Parliament Buildings.
Hard volcanic rocks, formed as lava flows, are widespread in the northern part of the North Island. There are also scattered occurrences on the eastern side of the South Island, especially near Christchurch and Dunedin. When labour was relatively cheap in the 19th and early 20th centuries, these rocks were used for construction. Trimming and dressing hard volcanic rock is time-consuming, and considerable skill is needed to lay these rocks, so the use of volcanic rocks declined after the First World War.
Banks Peninsula and the hills around Dunedin are both large extinct volcanoes that were built up in the Miocene Period, 10–13 million years ago. Numerous quarries were opened, and different rock types were tested as building stones. Christchurch probably has more stone buildings than any other city, partly because of the lack of timber in the surrounding area, as well as the availability of stone. Lava used for building stone in Dunedin is locally known as bluestone.
Fine-grained, dense black basalt from the western slopes of the Port Hills has been the dominant stone used in walls, steps and paving of Christchurch buildings since the mid-1860s, when a tramway was built to carry it into the city. Its source was a small volcanic cone, now quarried away. The quarry is closed, so Halswell stone can now be obtained only by recycling it from demolished structures.
Tuff is the geological name for ash that has erupted from a volcano and accumulated in the surrounding area. It is usually soft and easily worked, but most tuffs that have been quarried for building stone do not weather well, and are porous.
Volcanic breccia consists of fragments of rock in a matrix of ash that has been ejected from a volcanic vent. A large area of volcanic breccia is found around Port Chalmers in Otago Harbour, and has been quarried for use in a number of South Island buildings.
Ignimbite is formed by huge volcanic eruptions that violently eject large amounts of pumice and ash. Pyroclastic flows – dense, gas-charged clouds of ash – pour across the ground at high speed, depositing a sheet of pumice and ash. The resulting rock is called ignimbrite. Because the pyroclastic flows are ejected at high temperature, the resulting rock is often partly welded. Sheets of ignimbrite cover the central part of the North Island, but it has only been quarried for building stone in a few areas.
By 2005 the only working quarry was at Hinuera valley, near Lake Karapiro. Hinuera stone is cream, buff, or orange-brown, and contains fragments of pumice in a fine-grained matrix. It is hard enough to be used as a building stone, but soft enough to be cut, and is quarried in a similar way to Ōamaru Stone.
Ignimbrite was quarried from near Putaruru in the mid-20th century, and used in a number of government buildings around the country including Wellington’s old Dominion Museum (now part of Massey University).
Often grouped under the term granite, plutonic rocks have crystallised slowly at depth from magma. They are typically coarse-grained, with a variety of colours and textures.
Granite has symbolism as the hardest rock, implying permanence that lasts for centuries and through civilisations.
Imported plutonic rocks are widely used for polished decorative panels and facing stone. Local varieties have not been greatly used because material tested over the years has generally proved too weathered or broken. Most potential sources are in inaccessible parts of the South Island, and the cost of quarrying and trimming hard rock has been too great.
Only one plutonic rock type has been widely used. Coromandel granite (technically a tonalite or diorite) has been quarried from the northern end of Coromandel Peninsula, and used in many public buildings as a base course or as steps, and in monuments.
Although many churches and some other public buildings were built of stone in the 19th century, there are no national buildings made of stone from that period. In Wellington, memories of the destructive 1855 earthquake lingered, and although the new Government Buildings of 1876 were designed in the Italianate style, they were built in wood.
The Parliamentary complex in Wellington is a glorious mixture of architectural styles, all built in reinforced concrete. The neoclassical front of Parliament House, the central building, is faced with Tākaka marble, with a base course of Coromandel granite. This building was deliberately designed to display New Zealand materials, and marble and other local stones were used in the foyer and other public areas.
The Executive Wing of Parliament, commonly known as the Beehive, is an example of 1960s reinforced concrete design. To enhance the stark concrete, Tākaka marble has been used for decoration internally as well as on the lower external walls.
After the First World War there was a widespread desire to commemorate those who had died or been injured. Local committees and organisations all over New Zealand raised money for their own memorials, and decided how they were to be designed and built.
Overall there was less use of local building stone than might have been expected. Many memorials were built in concrete moulded to look like stone. Local stonemasons often opted to use polished slabs of imported stone. Many of the statues were imported from Italy where they could be obtained more cheaply than those quarried in New Zealand. Of the larger edifices, Auckland War Memorial Museum was built of imported Portland stone (limestone) from England, and the Bridge of Remembrance in Christchurch was built of Australian sandstone. Local rock was used for some of the smaller memorials, and the Blenheim memorial was built of rock from all around the Marlborough region.
In 1919 the Government voted £100,000 for a National War Memorial in Wellington – a huge sum in those days (equivalent to $NZ8 million in 2005). After considerable debate, it was agreed to build a complex that included a national art gallery, museum, and war memorial (including a carillon – a tower housing a set of bells) in the central suburb of Mt Cook. A competition for the design was won by the architectural firm of Gummer and Ford.
The complex made considerable use of New Zealand stone. Both the carillon and museum building (now part of Massey University) were clad with pinkish-brown Putaruru stone. Unfortunately the material was variable and weathered badly in places. It was removed from the carillon and replaced by Tākaka marble in 1982.
The Hall of Memories, beneath the carillon, is lined with cream Mt Somers stone. Inside, Hanmer marble, Coromandel granite and Tākaka marble are all used. Within the foyer of the old museum building, the columns are made of Whāngārei marble.
Several prime ministers have been commemorated with memorials made of local stone:
Hayward, B. W. Limestone and marble: a guide to building stones in New Zealand. Geological Society of New Zealand Guidebook 8, 1987.
Marshall, Patrick. Building-stones of New Zealand. DSIR Bulletin 11, 1929.
Maclean, Chris. For whom the bells toll: a history of the National War Memorial. Wellington: Heritage Group, Department of Internal Affairs, 1998.
Maclean, Chris, and Jock Phillips. The sorrow and the pride: New Zealand war memorials. Wellington: GP Books, 1990.
McLean, Gavin. Oamaru: history & heritage. Dunedin: Otago University Press, 2002.