New Zealand Steel’s Glenbrook Mill
A proud history built on iron-clad resolve.
Should anyone ever decide to turn the story of NZ Steel and its iconic Glenbrook Mill into a feature film, it might be best to give Sir Peter Jackson the heads-up early in the piece. With Sir Peter’s gift for the epic tale built on the good and the brave proving triumphant in the face of adversity, he’d be just the person for the job.
The dream of establishing a fully functioning iron and steel industry in New Zealand took hold almost from the very moment the plentiful reserves of ironsand were discovered on the west coast beaches of the North Island. Think around the time of early settlement.
Black ironsand was formed around 2.5 million years ago from rock deposited by volcanic activity in the Taranaki region. Hardly surprising then, that a number of early production efforts were centred around New Plymouth.
In the early days, through the mid to late 1800s and into the 20th Century, various Governments, both regional and central, offered bonuses and incentives to investors willing to build iron works.
Driven by these financial inducements, at least four companies were established prior to the 1st World War. These included:
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Pioneer Steel Works at New Plymouth (1869)
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New Zealand Titanic Iron and Steel at Te Henui Beach, New Plymouth (1873)
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New Zealand Iron and Steel Company at Onehunga (1883) and;
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New Zealand Iron Ore Smelting and Manufacturing Company at New Plymouth (1914)
All of these operations were eventually decommissioned because they failed to overcome a variety of technical issues related to the smelting process.
Across these and other ventures, a number of prominent businesspeople showed great determination that New Zealand could and would become a steel-making powerhouse in the image of Great Britain. That dream was easier said than done, however and, amongst many, one-time New Zealand Premier Julius Vogel lost a considerable amount of money through an ironsands investment.
Vogel was even heard to express the opinion that iron would never be profitably produced from ironsand.
Despite this widespread negativity, many kept trying, driven by a resolute belief in the value that a thriving steel industry would realise for New Zealand. The advancement of steel making was seen as important to the development of wider industries, the creation of jobs for the rapidly expanding population and for the promotion of a national sense of collective prosperity and progress.
New Zealand Steel, in the form it’s known today, was first established as a company in 1965 and the Glenbrook Mill was formally opened in 1970.
The long-term vision was a national steel industry that would be built upon and prosper from the utilisation of plentiful naturally-occurring resources. It seems, not much had changed from the early days.
Commercial operations began in 1968, with imported feed coil being used to produce GALVSTEEL® for local and Pacific Island markets.
At this time, the company was at the leading edge of technology allowing for the production of metallic iron through the direct reduction process. These speculative endeavours bore fruit in 1970, when enough confidence arose to allow for the commissioning of iron and steelmaking facilities at Glenbrook. These facilities would, initially, be utilised to produce billets for both domestic and export markets.
In 1972, a pipe plant was commissioned and, after this initial flurry of activity, a period of consolidation took hold before, in 1982, the COLORSTEEL® prepainting line was established.
With major investment through the 1980s, by 1987 New Zealand Steel was operating as a fully integrated steelworks.
In 1994, the existing continuous galvanising production line was modified to allow for the manufacture of ZINCALUME steel, in addition to traditionally galvanised products.
Today, the rich black sands of the North Island continue to underpin the steelmaking at Glenbrook.

More than 1300 full-time and semi-permanent contract staff ply their respective trades on the site.
The company is committed to continuous improvement on emissions and to the delivery of quality New Zealand-made products for local and global customers.
It has been a long and often arduous path to the innovative and active steel industry we know today. There is much to be gained from a study of the origins of the New Zealand steel industry, primarily the power of perseverance and of having a dream and following it to its successful conclusion.
But, that’s the thing. It’s not the conclusion. Because New Zealand Steel is as innovative and focused on the future as it ever has been. Long may that continue.
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