Derwentcote Steel Furnace

Derwentcote steel furnace was originally built in the 1730s and was used to make steel from wrought iron. It was in use for over 150 years, but fell into disrepair around 1890. English Heritage restored the site in 1990 and tours of the furnace have run in the past. However, it might be worth contacting English Heritage to find out when the tours might happen again.

The steel furnace was originally part of a complex, which included a pond, worker's cottages, forge buildings and a crucible furnace (for melting the wrought iron), all necessary for the cementation process.

The Derwent Valley was the perfect place for the industry, as the area had all of the natural resources needed to make the steel including charcoal, sandstone and coal.

To explain the process of making steel, we thought we would speak to an expert. So here is our (real-life!) in-house, semi-retired, metallurgist, Clive Clemens, to give us a brief insight into the cementation process:

"The process of cementation begins when wrought iron and charcoal were placed in one or more long stone pots inside a furnace and were heated up to 1100c. Bars of the wrought iron and charcoal were packed in alternate layers and made air tight in the pots.

Through time, the carbon atoms migrate between the gaps in the iron atoms - the longer the steel is held in the furnace, the further the carbon atoms travel towards the centre. The stone pots containing the steel were heated for a week or more. The pots were then left for 2 weeks to cool. In this time, the wrought iron gained around 1% in weight with the added carbon.

The bars of steel would then be heated and hammered, pressed or rolled to become shear steel."

We will be testing you on this later in the article.

Derwentcote produced over 100 tons of steel every year (which was no mean feat, as there were only two workers there!) and the steel was considered to be the best in Britain. However, the complex sadly closed in 1891 due to competition from the Sheffield steel industry and the introduction of new techniques in steel making.

It is a really interesting spot and is the last surviving piece of evidence of cementation steelmaking in the North-East. There is also a woodland walk accessible around the furnace, where you can see evidence of other buildings from the complex. I originally wrote this article in 2022, however, we visited during Heritage Open Days in September 2024 and got to have a peek inside.