Source: New Zealand Official Yearbook 2000. Please note, this information may now be out of date.
New Zealand contains a wide variety of minerals reflecting its diverse geology and dynamic tectonic history. While New Zealand is best known for its gold production (about 8 tonnes in 1998) there is also production of silver, ironsand, coal, aggregate, limestone, clay, dolomite, pumice, salt, serpentine, zeolite and bentonite. In addition, there are resources or potential for deposits of titanium (ilmenite beachsands), platinum, sulphur, phosphate, silica and mercury.
Minerals and coal in New Zealand can either be Crown or privately owned. All gold, silver, uranium and petroleum is owned by the Crown. The ownership of other minerals can be identified by Land Information New Zealand. Legislation controlling mineral production includes the Crown Minerals Act 1991 and the Resource Management Act 1991.
Gold is present as lode gold in quartz veins, as disseminated gold, finely dispersed through host rocks, and as alluvial gold in river gravels. In 1998 New Zealand produced 7.7 tonnes of gold. Alluvial gold mining occurs dominantly on the West Coast of the South Island and in Otago and Southland.
Mineral production, 1997–98
Historically, the Coromandel area had produced most of the silver mined in New Zealand. Production in recent years has been from the Martha Hill and Golden Cross mines.
New Zealand has a large resource of iron ore in the black sands of the west coast beaches between Greymouth and Westport in the South Island and from Wanganui to Muriwai in the North Island. Deposits of ironsand are currently mined at Waikato North Head and Taharoa by BHP New Zealand Steel.
Ilmenite and other heavy mineral sands
Ilmenite is a source of titanium dioxide which is used as an opacifier and a pigment in paint, paper, plastics, cloth and rubber and forms the basis of UV protection creams. Ilmenite black sands are present along the west coastline of the South Island. The largest known ilmenite resource is at Barrytown in Westland, where 50 million tonnes of potentially mineable sand has been defined.
Platinum group metals
An area of Southland which has produced platinum previously is being explored for platinum group metals.
Other metallic minerals
There are small deposits of manganese minerals in many localities. Some areas of Northland, Coromandel, Nelson and Westland have potential for base metals (copper, lead, and zinc) but there is currently little prospecting. Iron ore, stibnite (antimony), orpiment (arsenic), chromite, monazite, nickel and rutile have been mined in the past. Tin is known from Stewart Island. Bauxite is present in Northland where reserves of 20 million tonnes have been identified. Cinnabar, the principal ore of mercury, was historically produced in limited quantities from sinter deposits in Northland.
Aggregates are the product of a variety of rocks, gravels and sands used in road works and construction. Suitable rock for aggregate production is found throughout New Zealand. Its production is dominated by several large companies.
Clays are found throughout New Zealand and include bentonite, halloysite and kaolinite. They are used in the manufacture of sanitary ware, ceramics, bricks, tiles, pipes and pottery, as fillers in the manufacture of paper, paint, pharmaceutical and animal health products, and as pelletising agents.
Bentonite is used as a bonding agent and for specialist drilling products. It is found in substantial quantities in Hawke's Bay and Canterbury and is now being increasingly used in preference to imported bentonite.
Halloysite has been mined in Northland for more than 30 years. The clay from Matauri Bay is recognised worldwide as having an excellent colour and very high brightness and translucency when fired.
Dolomite rock is produced near Collingwood. It is used in agriculture and home gardening and shipped to Whangarei for use in glass making.
Limestone is found throughout New Zealand and is used in cement manufacture, roading, industry and agriculture. High quality limestone from Te Kuiti and Nelson is processed for export. Limestone is also used in New Zealand as a filler in the paint, glass, rubber, plastic and paper industries. Marble, a crystallised form of limestone, is mined in Nelson. It is used as a filler and in building construction.
At Lake Grassmere in Marlborough, salt is produced by the solar evaporation of sea water. About 60,000 tonnes is produced each year for New Zealand consumption.
Serpentine is a magnesium-rich rock used as a fertiliser additive and to manufacture decorative tiles. Deposits are mined at Wairere, and at Greenhills in the South Island.
Northland, North Auckland and Canterbury have deposits of silica sand which are mined for use in glass manufacture, foundry moulds and the building industry.
Sulphur, mainly used in production of agricultural fertiliser, has been mined from Rotokawa near Taupo.
Nephrite, popularly known as 'greenstone', is present in north Westland and northern Fiordland. A deposit of greenstone boulders in Olderog Creek, a tributary of the Arahura River has been the main source of greenstone recently.
The best known occurrences of bowenite, the serpentine variety of greenstone, are in Fiordland.
Ownership of the greenstone resource was recently returned to Ngai Tahu, the main South Island iwi, as part of their Treaty of Waitangi settlement.
Zeolite is mined at Ngakuru in the central North Island. It is used in horticulture and as animal litter.
Other non-metallic minerals
The following non-metallic minerals, some of which have been mined in the past, are also found in New Zealand: diatomite (industrial filtration), barite (industrial uses include glassmaking and fillers), asbestos (building material), feldspar (glassmaking, ceramics, enamels), magnesite (used in agriculture), mica (used in electronics), phosphate and sulphur (fertiliser), and wollastonite (paper, asbestos substitute, ceramics, adhesives and plastics).
Ministry of Economic Development - Crown Minerals
Quick Facts - Industries
back to top