A shaft of sunlight has penetrated a grubby skylight and settled on the black sandy foundry floor where, for the past 150 years, the iron backbone of British life has taken shape. 

Dust motes dance merrily in its beam; the air is rich with the acrid whiff of burnt sand.

Apart from the workers’ sleeve tattoos and the “toot” of a forklift as it passes with its cargo of molten iron – like a giant bucket of volcanic lava soup, it wobbles gently in its heavy bowl – practically nothing has changed since Arthur Ballantine & Sons was formally established in 1856.

“It’s a bit like what you imagine Mordor [Tolkien’s fictional world of Middle-earth] would be like,” says Gavin Ballantine, sixth generation boss of one of the few remaining foundries of its type in Scotland. 

A few years ago, the financial crisis meant Ballantine’s Bo’ness Iron Company was braced to follow the fate of hundreds of other foundries into collapse, until a last gasp buy-out in 2014 saw it reborn as Ballantine Castings. 

A few years on, and in a remarkable change of fortunes, its busy order book contains arguably one of the country’s most astonishing challenges 
– replacing the ironwork at the Palace of Westminster’s roof and Big Ben’s Elizabeth Tower. And it’s a mindboggling task. 

From the foundry’s corner of Bo’ness, West Lothian, about 1,000 iron tiles of varying size and shapes will be made from handcrafted moulds for the clock tower alone. The metal for each will be laboriously poured into handcrafted moulds. Once cooled and carefully finished, it will be handed to the conservation team tasked with overseeing the landmark tower’s five-year, £61 million restoration. 

“Everything from there to there is iron,” says Ballantine, pointing to an image of the roof above Big Ben’s famous clockface and up to its spiky tip.

“There are huge gutters too, so deep you could probably swim all the way around Big Ben.”

The Bo’ness foundry will also produce the tower’s gratings, stair treads and buttresses. Eventually, 600 tonnes of ironwork will pass through its gates bound for one of the top 10 “Instagrammed” places in the world.

It’s a major coup for the Scottish foundry and its 56 staff: the tower’s original ironwork was produced much closer to its home, at a foundry in Birmingham. 

At the same time, Ballantine Castings is making thousands of iron roof tiles for the Palace of Westminster. So far, it’s sent 3,300 south – a fraction of the “significant amount” Ballantine says the job will require. 

Along with earlier work on Westminster Bridge – so tricky that no other foundry in the UK even bothered to quote for the job – it adds up to a significant Westminster hat-trick for a family concern that can trace its roots to 1820.

One of about 150 foundries that existed in the Falkirk area, it powered through the Industrial Revolution and survived the age of plastic, only to be knocked off its iron pedestal by the banking crisis. 

Stung by losses and despairing at the need to lay off staff – some with skills that are almost impossible to replace – the 2014 buyout secured its future.
Running of the foundry passed from father Ian to son Gavin.

An English literature graduate, his father had tried to steer him away, fearing he may end up at the helm of a fading giant.

However, the call of the furnace, the need to keep a slice of industrial heritage alive and pride in knowing Ballantine’s incredibly ornate ironwork – even manhole covers are metallic works of art - was in the blood.

“You should see my father’s house, it’s covered in iron,” says Mr Ballantine. “He’d have a cast iron couch if he could.”

As he speaks, the furnace delivers another tub of liquid iron into the forklift’s waiting tub.

Magnesium has made it dazzlingly bright; too intense to look at for long, yet it’s hypnotically beautiful. As it slides into the tub’s hungry mouth, fiery sparks fly into the air. 

The crackling, smoking cascade of tiny fireballs is like an enormous Guy Fawkes’ sparkler that no-one would ever want to touch – the molten iron that sloshes into the giant tub has reached 1700˚C, a drip would burn straight through skin, nerves and muscle.

The process – the melting of scrap iron to create a tonne of molten metal that is divided into tubs to be poured or scooped using giant ladles into moulds and left to cool – is 80 per cent what it was in Ballantine’s great-great-great grandfather’s day. 

His very first order, in a handy link to today’s Westminster task, was for seven miles of balustrading to line the Thames Embankment, including the city’s famous “dolphin” lamp standards. “That was the first big job, and it stayed that way,” he says.

Generation after generation of Ballantines and Bo’ness foundry workers – fathers, sons, uncles and brothers - went on to produce grand, ornate ironwork for some of Britain’s most familiar bridges and railings, thousands of postboxes and lampposts.

From everyday cookers to window frames and manhole covers to the remarkably detailed ironwork canopy that shelters visitors to Buckingham Palace, and the restored cast iron frame of the Venetian-inspired Ca D’oro building in Union Street, Glasgow. 

“My grandfather used to say ‘you’re never further than 100 paces away from one of our castings’,” says Mr Ballantine.

He put the theory to the test recently in Edinburgh. By the time he had passed 100 tonnes of ironwork gracing the entrance to Waverley Station, North Bridge’s refurbished parapet castings, railings on the octagonal tower of the former Scotsman building and around the National Galleries of Scotland, the spear-head railings at Edinburgh Castle Esplanade and the 15 cast iron replica cannons inside, the point had been much proven.

As well as tackling Westminster’s world-famous structures, Ballantine Castings - only a few miles from the grounds of Kinneil House, where James Watt perfected his steam engine and kickstarted the industrial revolution - is creating a new wave of ironwork. 

Using traditional methods and drawing on its stash of around 200,000 patterns, its cast iron is in demand across the world.

Ballantine is particularly proud of the 260m of railings and ramps sent to Stockholm’s national museum, the firm’s first job in Russia, 40 ornate cast iron urns sent to France, and over a kilometre of railings for Norway. 

Recently the foundry supplied 30 bespoke cast iron columns for St Vincent and the Grenadines in the Caribbean.

They’ll be in public view, a cast iron façade for a very private property in St Andrews, is not Requests like those are increasing, fuelled by architects who have embraced its cast iron’s “green” credentials.

“There’s something of a renaissance happening,” adds Mr Ballantine. “People are realising the scrap metal we buy to melt down was probably made 200 years ago and that we can make last another 200 years.”