Telford Slags

Telford has more old slags than anywhere else in the world. As the birthplace of the industrial revolution it is not surprising that the area that is now Telford has a large repository of historical slag. Slag is the waste product left behind from the smelting of iron, and in Telford, it’s everywhere.

The slag tips of the Old Park Ironworks, scene of the Cinderloo riots of 1821, photographed in 1965

Slag has a defining and unique role in the history and topography of the town. From ‘Slag tip to forest city’ is a strap line that summarises the transformation that the town has undergone over the past 200 years and highlights why the word ‘slag’ has a particular association with Telford. Our paths are not paved with gold but frequently the shining blue, green, purple and black gemstones, or slag, created in the industries that shaped the industrial revolution.

Footpaths paved with slag

In its natural state iron is found in combination with sandstone and other minerals. The rust coloured, heavy stone is not much use to us in that form, but heating it in controlled conditions to 1250C separates the metallic iron from the material we don’t want. Some of it is given off as gas and some melts into a hard, durable, glassy, blue-green to black substance, slag, the by-product, the valueless waste.

Telford slag created at 1250 degrees C

The term slag has a modern usage which avoids the town celebrating what is perhaps its most intrinsic characteristic. Who knew that the Museum of Iron hosts the National Slag Collection? Another one of the towns best kept secrets!

The national slag collection housed at the Museum of Iron

John Box the ecologist employed by Telford Development Corporation to protect and enhance some of the towns ecological legacy spoke recently of the fascinating backdrop that slag provides across the town. The pit mounds, the heath lands and formally pitted areas of Dawley, Oakengates, Donnington and Madeley provide diverse and unique habitats linked to the industries that made the area great.

John Box describing the ecology of slag in front of ‘Slag bear’ at Blists Hill

The hard labour combined with science and technology provide a chemistry lesson, recently delivered by Mike Dobby, of how under our feet the application of revolutionary industrial methods that set the town at the heart of the industrial revolution. The shiny green and blue pieces of slag that we are familiar with tell a tale of previous generations ingenuity in helping to create the tools and machines that moved the area on from a rural back water to a place renowned for its pioneering work.

Mike Dobby describing the chemistry of slag

But with some irony the transformation of the former waste generated from the mining and quarrying of coal, iron ore, limestone and clay is now fiercely protected by the local community who fear the loss of the habitats that have grown on and out of these formally brutal working environments.

The Portley road pit mound gained notoriety as a handmade sign proclaiming ‘Dawley wood’ stood proudly at the top of the mound in defiance of the bull dozers that subsequently raised it to the ground. The welcome development of nature reserves across the town are each a history and ecology lesson that tells a story of natures ability to reclaim space from humans and regenerate in the most difficult environments.

The Dawley Wood sign on top of Portley road pit mound before the bulldozers arrived

 Residents in Lawley Gate uncovered recently different types of ‘Telford slag’ amongst the bricks and mortar of a former well. Tony Mugridge talks passionately of the hard surfaces that provide glimpses of the labouring activities that went on around us. When you look closely slag forms many old walls in the area and the foundations of much of Telford’s highways are taken from the slag and clinker created out of the mines and foundries upon which the new town is built.   

Tony Mugridge describing Telford slags found in Lawley Gate well

The town park, the ‘Jewel in Telford’s crown’   hosts a small information board entitled ‘ Slag works’ telling the story of Wrekin Chemical works and the ‘ slag crusher’ installed by H.C. Johnson to  create aggregate for roads and concrete manufacture.

Slag works display in town park

Our project Cinderloo gained its name from the setting where the battle between the colliers and yeomanry took place on the cinder hills (slag heaps) at Old Park. Tom Palin was tried and hung for his role in the events, which included men and women throwing pieces of clinker (slag) in self defence against the bullets and bayonets of the yeomanry.

Slag plays a central

The image of Tom Palin dangling from a rope, described by the local press of the time as ‘……….’ In modern language a slag of a human being, literally hung out to dry is perhaps a metaphor for what slag is to Telford – the embodiment of industrial capitalism scraping the top off the smelting iron  and casting it aside as the human collateral of its profits or perhaps the salt of the earth and of regeneration – a fight for social and environmental justice that is the enduring battle that Cinderloo 1821 is attempting to rekindle.

#telfordslags anyone?

6 thoughts on “Telford Slags

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  1. magical article, but not as magical as my adventures as a boy. i was surrounded by unadopted and nature reclaimed slag heaps, unused railway lines and the weathered relics of a bygone age. my young cohorts and i left no stone unturned as we played endlessly and recklessly in the cobwebs of a unique environment.

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  2. It is quite amazing how the local area has changed from the chimney belching slag heap town of the Industrial Revolution into a relatively green and pleasant landscape. We never know how many pit shafts lie under our homes, as the majority were never mapped. I’m sure another road will collapse of a large tree will disappear into a sink hole in the not too distant future. Our ancestors were heroes, who toiled both above and below ground, for a hand to mouth existance. That was real poverty!


    1. Thanks for your comment Paul. You’re old mate Pete J here. Are you still metal detecting? We are interested in stuff from 1821. Miners tokens/ beer tokens etc. Hope you are keeping well:)


  3. Round the back of the “Aga”, where the scrap steam locomotives waited for re-melting, that’s where the brightest slag was. Oil from the scrap mixed and lubricated the freshly broken Allied Ironfounders slag into rainbow colours. It’s great to read an appreciation of something so few now know of.


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