Skip to content

COR-TEN® Steel

Post date:

The first known use of COR-TEN® steel in the architectural world was the John Deere World Headquarters in Moline, Illinois. Completed in 1964, it was designed by Eero Saarinen. 

The habitation innately preferred by people has had a significant effect upon landscape architecture. believed by many researchers to have originated during prehuman evolution in the African savanna forest, the predilection includes dwelling on a height that is near a body of water and looks down on fruitful parkland (with large animals in sight, even if only represented by sculpture).
The habitation innately preferred by people has had a significant effect upon landscape architecture. believed by many researchers to have originated during prehuman evolution in the African savanna forest, the predilection includes dwelling on a height that is near a body of water and looks down on fruitful parkland (with large animals in sight, even if only represented by sculpture).

Hmm, yes, that’d be the same John Deere building mentioned in the WE ♥ PLANTS post, only now it’s not the neo-savanna landscape we’re looking contentedly at.

Media Assassin! Thanks for pointing me to the fab pic.

The John Deere building is the first use of Cor-Ten® steel in the architectural world, but it’s also one of the first uses of post-modern colour in the architectural world although, as with much of post-modernism, nobody knew it at the time. I contend the first use of post-modern colour was the Seagram Building, completed in 1958. “How so?,” you ask?

seagram-building-exterior Post-modern use of colour: A clue. FLW used to refer to this building as Mies’ “whisky building”. The famously and expensively contrived colour of the steel could, if one were so inclined, cause one to think of the colour a whisky bottle – especially upon seeing its amber-tinted contents through the glass. If the unique colour of the building evokes the idea of whisky, that idea acts in three different ways that, together, reference something. The building is an advertisement, after all. 

  1. The colour of the building looks different from that of any building around it. 
    1. The colour of the building evokes a notion of being different from that of any building known (to architectural cognoscenti) to have ever existed. It is novel, in other words.
    2. The colour of the building evokes an affinity with its location – 1960’s New York, perhaps as a sophisticated whisky-drinking city. 
    3. The colour of the building evokes a notion of the colour of something not a building – in this case, the colour of whisky.  

After this building, colour came to “mean stuff” and it was all downhill from there, (especially once shape came to the party). But it’s amazing how CEOs could almost instantly see what Mies was doing, yet architectural historians still can’t. History is silent on whether the whisky colour was Mies’ idea or that of the CEO’s daughter, Phyllis Lambert, who “was influential in bringing Mies onto the project” [W] but given M’s reputation as Mr. Less-is-More, the wilful addition of bronze as a colour was either corporate brown-nosing if his idea, or corporate kow-towing if hers. Possibly a bit of both as the CEO liked bronze as a colour, if not its cost. 

And so with Deere, it’s unclear whether the use of COR-TEN® steel was Saarinen’s idea, or that of William Hewitt, the president of Deere & Company. Hewitt definitely wanted his headquarters to have an “earthy” look. John Deere is a very earthy company.


Committed to those linked to the land

Over the past 175 years, John Deere has seen a great many changes in its business, its products, its services. Change always comes with opportunity. And Deere has always been ready and willing to embrace it. Yet, through it all, John Deere is still dedicated to those who are linked to the land – farmers and ranchers, landowners, builders.

Before going any further, I should mention that COR-TEN® steel is steel that, because of its chemical composition, forms a protective  layer of rust prevents it from rusting further and thereby eliminating the need for other coatings such as paint. This is a good thing. Q: Imagine if the Farnsworth House had been built of COR-TEN® steel – how would we then think of it? A: We would think of it as earthy and natural instead of pure and pristine. (WARNING: Don’t try this at home! When COR-TEN® steel is welded, it’s difficult to get the welds to weather at the same rate.)

The fact that COR-TEN® steel looks earthy and old instead of pure and pristine is seen as a positive quality – as if steel has suddenly become like trees, only better. Did you know that in Denmark all masts for supporting the catenary on electrified railways are made of COR-TEN® steel for aesthetic reasons? It’s true – here’s a pic!

Railway-electrification COR-TEN® steel has been around for years now so although it’s not novel anymore, you can still build something strong, quick and brown – which, aesthetically, is almost as good as green, it seems.

But buildings also exist in the dimension of Time and this is where COR-TEN® steel gets interesting. Normal steel will rust over time if left exposed and unprotected. The charm of COR-TEN® steel for architects is that it can provide the appearance of age in a relatively new building. corten colour True, this appearance of age doesn’t happen overnight but, since it’s artificially accelerated, it soon becomes an example of colour and pattern not looking new (WAS NOW), and giving the impression that the building is older than it really is (an idea of NOT NOW). I call this combination of reality and idea DISGUISE because the building’s place in time is disguised – at least as far as colour and pattern are concerned.

The charm of this next building, Rick Joy’s Desert Nomad House is largely due to the physical properties of COR-TEN® steel making it ASSOCIATE with its landscape via the artificially natural colour and pattern of the staining. Time-wise, the building appears to have been there for longer than it actually has. It has “settled in” in time.

There are historic precedents for this. The best example I can think of is in The Victorian Country House by Mark Girouard (1979) – I’ve rarely been without a copy.

4380810ae7a00e6add023210.L._SY300_[I’ve ordered another copy and will add this information later, but] an architect was extending a mock-Tudor mansion by using an earlier and heavily half-timbered version of Tudor because (I paraphrase) “Tudor so quickly passes from the new to the old”. Tudor came into and out of fashion several times, and always because of the accelerated weathering of its timbers. In this next example, the real Tudor building is Queen Elizabeth’s Hunting Lodge (1542) on the right. In the middle is a Victorian addition circa 1850 and to the left is the 1912 replacement of a pub that burned down. QUEEN ELIZABETH'S HUNTING LODGEThe Tudor Revival for the 20th century, COR-TEN® steel, gives buildings a gravitas through the appearance of having stood some test of time. Like the Rick Joy house, this next building by Simon Ungers uses the physical colour and pattern of COR-TEN® steel to evoke notions of “natural” which are strongly contradicted by the very unconventional shape. (“Is it a house?”)

124276865_bd897da1eaThis next image features the same combination of natural colour and unnatural shape, in a natural landscape

ballale-betty-frontand, to a lesser extent, the Danish railway structures do too. It’s a desirable effect – it softens and validates shapes, excuses them. This third example is Jean Nouvel’s Swiss Pavillion for Expo 2002. Like the Ungers house above, it’s an example of a future artefact – both new and old at the same time. Again, colour and pattern may have weathered, but shape shows none of these ravages of time. (This “temporal signature” has nothing to do with its monumentality – that’s a physical phenomena resulting from the contrived absence of scale indicators such as doors and windows.)


This very same quality of accelerated ageing is also what makes COR-TEN® steel a popular choice of material for sculpture, both urban and otherwise. I googled CORTEN SCULPTURE so now you won’t have to. You knew what to expect anyway.

Untitled COR-TEN® steel is not only the material of choice for public art, but also for more private artworks. Zen Metal Art, for example, has a range of metal artworks that will enhance your landscape or garden.


Corten steel art is also referred to as rusted steel art or weathered steel art. The colours generated by the ageing steel blend beautifully with foliage colour and provide an organic, “rustic” element within the Landscape.

As does CDS Architectural Metalwork.


Unfortunately, the temporal associations of COR-TEN® steel have become associated with a pointless gravitas in much the same way as Barber’s Adagio for Strings has become shorthand for “feel sad now”.


We can’t rule out a COR-TEN® steel revival sometime in the future but,
for now, best give it a rest, until 
Nature finishes, the job man started, and COR-TEN® steel, rusts away for real.

• • •

The United States Steel Corporation (USS) holds the registered trademark on the name COR-TEN even though it sold its plate business in 2003 to the International Steel Group which was created after the turnaround fund, WL Ross & Co. LLC, purchased LTV (Ling-Temco-Vought) Steel in February 2002 and merged its assets with those of Weirton Steel. In 2005, the International Steel Group was acquired by Mittal Steel which, in 2006, merged with Arcelor to become the world’s largest steel company, ArcelorMittal. 

No COR-TEN® steel was used in the construction of the ArcelorMittal Orbit



  • The Seagram building is not clad in cor-ten, but in bronze. You do seem to imply, when talking about bringing an impurity into the steel, that it is cor-ten, however. I find that a bit confusing; the date of 58 is right, so that would have made it a predecessor to Eero Saarinen (1964). In “Building Seagram” Lambert does talk about the colours, which may be of interest to you.

    • Hello Thomas, I’ve edited my post so it’s a bit clearer – for now. I did find this info here “Set on bronze-clad pillars, the 38-storey facade consists of alternating bands of bronze plating and “whisky brown”-tinted glass (the material and colour choices were a result of Bronfman’s insistance of having a warmer-toned facade than in the Lake Shore Drive Apts).” At least now I know that it was Bronfman, not Mies who wanted warm.

      But I’m still not sure if those external I-beams are bronze-clad steel, bronze-coloured steel or actual bronze. I’m told that 1,500 tons of bronze were used, so actual bronze seems unlikely. I’m probably going to have to buy Building Seagram to find out. (Building Seagram is a cunning title for a CEO’s daughter – that’s what she certainly did!)