1. What is Ganister?
Ganister (also spelt with double n) is a hard, fine-grained and high-in-silica-content quartzose sandstone. Over the years, it has been mined and quarried due to its use as the main constituent in the manufacture of refractory or silica bricks, used to line furnaces. It is commonly found as seatearths (a layer of sedimentary rock underlying a coal seam) within English Carboniferous coal measures which date back 280 million years. Due to its position in the geographic strata, it is typically penetrated by root traces which appear as pencil-like streaks, giving rise to the name “pencil ganisters”.
It is a heavy rock and varies in colour from light to dark grey and pink. Due to this, it is hard to identify. Sometimes it is also referred to as “true ganister”. It is primarily made up of between 90-96% silica, with the remaining percentage typically consisting of alumina, lime and iron peroxide. Other ‘fireclays’, including pot clay, are often found beneath the ganister seam and hence lower down in the rock time series. They are more ‘plastic’ in nature, due to their higher alumina content.
Once mined, the ganister has to be ground-up and crushed into a fine dust. It is then mixed with water and blended into a thick clay which, in turn, is then placed into brick moulds and baked in a kiln. A bricklayer would then use the bricks to line the furnace with.
2. Ganister in Sheffield
Locally, ganister rock can be found beneath the so-called “Hard Halifax Bed” coal seams found to the north of Sheffield. The first mentions of ganister from an historical perspective can be traced back to the details of an 1817 property auction, although quarrying of ganister developed as far back as the middle of the 17th century. Later expansion of farming in the area north-west of Sheffield brought the need for farmhouses and cottages to be built for the workers, leading to ganister being used as a building material.
It wasn’t until the 1850s onwards that the demand for ganister (for a completely different usage) started to really take-off. Sheffield had been a centre for the manufacture of iron for a number of centuries with fireclays, such as pot-clay, used in the iron manufacturing process to line ingots etc. Prior to the use of gannister, the Stannington valley on the western extremities of city provided a ready source of pot-cay. Up until then, despite its superior refractory properties compared to pot-clay, the difficulty with using ganister for these purposes came down to the fact that it needed to be ground down before it could be formed into refractory products.
In his writings in 1923, W.J. Rees attributed the first use of ganister as a refractory material to Benjamin Huntsman (1704-1776), who was also the first person to cast steel in clay-pot crucibles, circa 1750. Rees records that he sourced the gannister by scraping it off the road surfaces! While this is open to conjecture, what is certain is that the patenting of the Bessemer convertor in 1855 by Henry Bessemer (1813-1898) revolutionised the steel-making process and dramatically increased the demand for superior fireclays, such as gannister, in order to line the massive convertors. This, coupled with widescale mechanisation of industrial processes to aid the crushing of ganister and better rail links to facilitate its transportation, meant that the supply of ganister-based refractory bricks would be able to keep up. Thus it transformed the value of gannister which had previously bore little economic value or use beyond building field boundary walls and the surfacing and repairing of roads.
The Bessemer convertor that stands outside Kelham Island museum in Sheffield:
The sourcing of ganister prior to this up-surge in demand was through quarrying ganister steams that were close to the surface. Undoubtedly, it was also being mined in the early 1800s, but only on a small scale. Records show that ganister was being quarried near Deepcar and being sold to Messer’s Huntsman, Ibbotson & Co and to Thorncliffe ironworks. The largescale use of gannister was initiated by Messrs. Head and Dransfield to supply the ever-expanding demand from the steel-making industry. Other local companies, such as Bramall’s, also took the opportunity to diversify their activities into ganister production and were the first to realise the full-commercial potential of ganister-made refractory products in the 1850s.
The making of refractory bricks from ganister was similar to making bricks from other fireclays. The stone was washed in order to remove traces of any other clays in order to facilitate crushing. It was then broken up by hammer into smaller pieces, before being fed into a mechanical crusher. Lime was also added to the ganister while in the crusher to produce “ganister plug”. It was then graded using 2-inch mesh screens before being fed via a chute into the grinding mill. The grinding process involved a circular ‘wet pan’ where the ganister was ground with water. The machines had either a fixed pan with rotating rollers or a rotating pan with fixed rollers. An example of the former manufactured by Smedley’s of Belper in 1945 is pictured below outside Kelham Museum, Sheffield:
The slurry was then shaped into bricks, either by hand and latterly by machines, left to dry in a drying shed before being fired in a kiln. Kilns were either of the beehive type (as seen at Caledonia works) or tunnel kilns (at Storrs fireclay works). The process of “burning” sometimes lasted up to 6 days where kilns containing up to 50,000 bricks reached temperatures of 1,500 degrees Centigrade.
From the mid-1800’s until the inter-war period, ganister mining thrived in the area, often extracted in conjunction with coal from so called “mixed mines”. The Worrall, Wadsley and Loxley areas of Sheffield held the distinction of being the source of best quality “true” ganister in the UK. Seams varied from 6” to 5ft and tended to be thicker than the overlaying coal seams, which ranged from non-existent up to 2ft 6”. Below the ganister, fireclay seams of similar thickness could also be found.
There were three ganister mines in the immediate area of Worrall. The Yews Mine and the Langhouse Mine were owned by Charles Bramall, while the Stubbin Mine was owned by the Oughtibridge Silica Firebrick Company and was the last to close in November 1927. The Bramall Company owned 2 silica brickworks in the area - Birkin Works and Caledonia Works, but both had closed by 1927.
There were three firms with interests in the Loxley Valley and between them, they supplied 95% of all the hollow refractories made in the steel works all over Great Britain. They were Dysons, Thomas Marshall’s and Thomas Wragg and Sons. Mining was a very wet job and the mines were constantly being flooded.
While many ganister and fireclay mines closed in the 1930s and 1940s, some struggled on. Wragg’s fireclay mine in Ughill finally shut in 1977 while opencast ganister extraction ended at Dyson’s Loftshaw quarry in the 1980s.
3. The Project
My interest in the ganister and pot-clay mines of Sheffield was first piqued by @tarkovsky and his report on a ganister mine near Oughtibridge back in November 2017. Around the same time I visited a pot-clay mine in Loxley and then in the ensuing months I spent many-an-hour searching for mines in Wharncliffe Woods. The real game changer was when I found out about a book called “The Forgotten Mines of Sheffield” by Ray Battye in August 2020. Having ordered it on-line, I read it from cover-to-cover. It’s a frustrating book. It’s packed full of information but the photo reproduction is terrible. Also the info about what remains of the mines today and where the remains are is extremely limited. At the time we’d already gone into lockdown and with restrictions in place and preventing travel outside of the local area, I embarked on a project to locate all the remaining ganister and fireclay mines of Sheffield and document them. This led to numerous trips to the North and West of Sheffield. Ray Battye’s book was used in conjunction with old OS maps to locate potential remains and then followed by hours of walking, scrambling over rocks and yomping through undergrowth. Much of the time, the rewards were small as, in most cases, the traces of this once prosperous industry have all but vanished off the face of the landscape. Occasionally, however, the land gave over its secrets.
What follows, spread over the following five reports, are my findings divided up by area:
1. Stocksbridge, Deepcar and Wharncliffe
2. Oughtibridge and Beeley Wood
3. Ughill and Bradfield
4. Wadsley, Worrell and Loxley
5. South of Sheffield
The pictures in the following reports are far from spectacular. Sometimes it’s just a pile of stones or an overgrown, stone-lined approach to a long-gone adit. Hopefully though, they provide an extensive document and record of the scant remnants of this once vital industry, before they are gone and lost forever.
1. Stocksbridge, Deepcar and Wharncliffe
The mines in this area are predominantly ganister mines, whoever, both coal and ganister was mined from a number of them. In 1908, records stated total output from the valley to be circa 40,000 tons.
(A) Henholmes colliery and mines
Henholmes colliery was located in Stocksbridge. It was also known as Ellen Cliff and also produced coal. It opened in 1864 under the ownership of John Armitage and remained open until the start of World War 2 (1939). Born in 1826, Armitage owned two mines in Deepcar, Henhomes being the smaller of the two. It’s small mine employed only three people in 1896 and managed by a Mr. F Coultas.
O/S map of Henholmes:
Overview of the factory in 1890. Note Wharncliffe Villa to the left-hand side, the beloved home of John Armitage:
Today the remains are few and far between. There’s a number of retaining walls, a pack trail and a bricked-up adit. Most of the remains, however, are enveloped by ivy, making it difficult to get a real feel for the site. Hence the photos from here are a bit underwhelming:
The bricked-up adit close to the factory:
Retaining walls, cleared of ivy:
Miner’s track up the bank, now part of a footpath:
After searching for more adit entrances to no avail we finally gave up. Hence that’s it for Henholmes.
(B) Hollin Busk Mine
Located on Hollin Busk Lane above Stocksbridge, this was a mixed mine, with both coal and fireclay being extracted from this small shaft mine. Records state that the shaft reached coal at 108 feet and pot clay lower down in the strata at 261 feet. A ventilation shaft was also sunk circa 1900. The whole mine had closed by 1930.
The capped-off winding shaft, brick mounted headgear and wheel hand and adjacent winch survived for many decades became a familiar sight for motorists, before being demolished in early 2017 and the whole site landscaped as an iconic part of the valley's heritage was lost. The owners stated the wheel was being restored so it can be placed at the entrance to the site.
At the time when I came here, I didn’t know the headstock had been demolished. I couldn’t see it anywhere. Then, from the corner of my eye say the old wheel in the corner of yard of a nearby farm. At this stage, the penny dropped. So nothing too impressive by way of photos from this lovely little mine.
The now damaged wheel:
Sitting forlornly in the winter snow:
And some former brick work:
Ganister (also spelt with double n) is a hard, fine-grained and high-in-silica-content quartzose sandstone. Over the years, it has been mined and quarried due to its use as the main constituent in the manufacture of refractory or silica bricks, used to line furnaces. It is commonly found as seatearths (a layer of sedimentary rock underlying a coal seam) within English Carboniferous coal measures which date back 280 million years. Due to its position in the geographic strata, it is typically penetrated by root traces which appear as pencil-like streaks, giving rise to the name “pencil ganisters”.
It is a heavy rock and varies in colour from light to dark grey and pink. Due to this, it is hard to identify. Sometimes it is also referred to as “true ganister”. It is primarily made up of between 90-96% silica, with the remaining percentage typically consisting of alumina, lime and iron peroxide. Other ‘fireclays’, including pot clay, are often found beneath the ganister seam and hence lower down in the rock time series. They are more ‘plastic’ in nature, due to their higher alumina content.
Once mined, the ganister has to be ground-up and crushed into a fine dust. It is then mixed with water and blended into a thick clay which, in turn, is then placed into brick moulds and baked in a kiln. A bricklayer would then use the bricks to line the furnace with.
2. Ganister in Sheffield
Locally, ganister rock can be found beneath the so-called “Hard Halifax Bed” coal seams found to the north of Sheffield. The first mentions of ganister from an historical perspective can be traced back to the details of an 1817 property auction, although quarrying of ganister developed as far back as the middle of the 17th century. Later expansion of farming in the area north-west of Sheffield brought the need for farmhouses and cottages to be built for the workers, leading to ganister being used as a building material.
It wasn’t until the 1850s onwards that the demand for ganister (for a completely different usage) started to really take-off. Sheffield had been a centre for the manufacture of iron for a number of centuries with fireclays, such as pot-clay, used in the iron manufacturing process to line ingots etc. Prior to the use of gannister, the Stannington valley on the western extremities of city provided a ready source of pot-cay. Up until then, despite its superior refractory properties compared to pot-clay, the difficulty with using ganister for these purposes came down to the fact that it needed to be ground down before it could be formed into refractory products.
In his writings in 1923, W.J. Rees attributed the first use of ganister as a refractory material to Benjamin Huntsman (1704-1776), who was also the first person to cast steel in clay-pot crucibles, circa 1750. Rees records that he sourced the gannister by scraping it off the road surfaces! While this is open to conjecture, what is certain is that the patenting of the Bessemer convertor in 1855 by Henry Bessemer (1813-1898) revolutionised the steel-making process and dramatically increased the demand for superior fireclays, such as gannister, in order to line the massive convertors. This, coupled with widescale mechanisation of industrial processes to aid the crushing of ganister and better rail links to facilitate its transportation, meant that the supply of ganister-based refractory bricks would be able to keep up. Thus it transformed the value of gannister which had previously bore little economic value or use beyond building field boundary walls and the surfacing and repairing of roads.
The Bessemer convertor that stands outside Kelham Island museum in Sheffield:
The sourcing of ganister prior to this up-surge in demand was through quarrying ganister steams that were close to the surface. Undoubtedly, it was also being mined in the early 1800s, but only on a small scale. Records show that ganister was being quarried near Deepcar and being sold to Messer’s Huntsman, Ibbotson & Co and to Thorncliffe ironworks. The largescale use of gannister was initiated by Messrs. Head and Dransfield to supply the ever-expanding demand from the steel-making industry. Other local companies, such as Bramall’s, also took the opportunity to diversify their activities into ganister production and were the first to realise the full-commercial potential of ganister-made refractory products in the 1850s.
The making of refractory bricks from ganister was similar to making bricks from other fireclays. The stone was washed in order to remove traces of any other clays in order to facilitate crushing. It was then broken up by hammer into smaller pieces, before being fed into a mechanical crusher. Lime was also added to the ganister while in the crusher to produce “ganister plug”. It was then graded using 2-inch mesh screens before being fed via a chute into the grinding mill. The grinding process involved a circular ‘wet pan’ where the ganister was ground with water. The machines had either a fixed pan with rotating rollers or a rotating pan with fixed rollers. An example of the former manufactured by Smedley’s of Belper in 1945 is pictured below outside Kelham Museum, Sheffield:
The slurry was then shaped into bricks, either by hand and latterly by machines, left to dry in a drying shed before being fired in a kiln. Kilns were either of the beehive type (as seen at Caledonia works) or tunnel kilns (at Storrs fireclay works). The process of “burning” sometimes lasted up to 6 days where kilns containing up to 50,000 bricks reached temperatures of 1,500 degrees Centigrade.
From the mid-1800’s until the inter-war period, ganister mining thrived in the area, often extracted in conjunction with coal from so called “mixed mines”. The Worrall, Wadsley and Loxley areas of Sheffield held the distinction of being the source of best quality “true” ganister in the UK. Seams varied from 6” to 5ft and tended to be thicker than the overlaying coal seams, which ranged from non-existent up to 2ft 6”. Below the ganister, fireclay seams of similar thickness could also be found.
There were three ganister mines in the immediate area of Worrall. The Yews Mine and the Langhouse Mine were owned by Charles Bramall, while the Stubbin Mine was owned by the Oughtibridge Silica Firebrick Company and was the last to close in November 1927. The Bramall Company owned 2 silica brickworks in the area - Birkin Works and Caledonia Works, but both had closed by 1927.
There were three firms with interests in the Loxley Valley and between them, they supplied 95% of all the hollow refractories made in the steel works all over Great Britain. They were Dysons, Thomas Marshall’s and Thomas Wragg and Sons. Mining was a very wet job and the mines were constantly being flooded.
While many ganister and fireclay mines closed in the 1930s and 1940s, some struggled on. Wragg’s fireclay mine in Ughill finally shut in 1977 while opencast ganister extraction ended at Dyson’s Loftshaw quarry in the 1980s.
3. The Project
My interest in the ganister and pot-clay mines of Sheffield was first piqued by @tarkovsky and his report on a ganister mine near Oughtibridge back in November 2017. Around the same time I visited a pot-clay mine in Loxley and then in the ensuing months I spent many-an-hour searching for mines in Wharncliffe Woods. The real game changer was when I found out about a book called “The Forgotten Mines of Sheffield” by Ray Battye in August 2020. Having ordered it on-line, I read it from cover-to-cover. It’s a frustrating book. It’s packed full of information but the photo reproduction is terrible. Also the info about what remains of the mines today and where the remains are is extremely limited. At the time we’d already gone into lockdown and with restrictions in place and preventing travel outside of the local area, I embarked on a project to locate all the remaining ganister and fireclay mines of Sheffield and document them. This led to numerous trips to the North and West of Sheffield. Ray Battye’s book was used in conjunction with old OS maps to locate potential remains and then followed by hours of walking, scrambling over rocks and yomping through undergrowth. Much of the time, the rewards were small as, in most cases, the traces of this once prosperous industry have all but vanished off the face of the landscape. Occasionally, however, the land gave over its secrets.
What follows, spread over the following five reports, are my findings divided up by area:
1. Stocksbridge, Deepcar and Wharncliffe
2. Oughtibridge and Beeley Wood
3. Ughill and Bradfield
4. Wadsley, Worrell and Loxley
5. South of Sheffield
The pictures in the following reports are far from spectacular. Sometimes it’s just a pile of stones or an overgrown, stone-lined approach to a long-gone adit. Hopefully though, they provide an extensive document and record of the scant remnants of this once vital industry, before they are gone and lost forever.
1. Stocksbridge, Deepcar and Wharncliffe
The mines in this area are predominantly ganister mines, whoever, both coal and ganister was mined from a number of them. In 1908, records stated total output from the valley to be circa 40,000 tons.
(A) Henholmes colliery and mines
Henholmes colliery was located in Stocksbridge. It was also known as Ellen Cliff and also produced coal. It opened in 1864 under the ownership of John Armitage and remained open until the start of World War 2 (1939). Born in 1826, Armitage owned two mines in Deepcar, Henhomes being the smaller of the two. It’s small mine employed only three people in 1896 and managed by a Mr. F Coultas.
O/S map of Henholmes:
Overview of the factory in 1890. Note Wharncliffe Villa to the left-hand side, the beloved home of John Armitage:
Today the remains are few and far between. There’s a number of retaining walls, a pack trail and a bricked-up adit. Most of the remains, however, are enveloped by ivy, making it difficult to get a real feel for the site. Hence the photos from here are a bit underwhelming:
The bricked-up adit close to the factory:
Retaining walls, cleared of ivy:
Miner’s track up the bank, now part of a footpath:
After searching for more adit entrances to no avail we finally gave up. Hence that’s it for Henholmes.
(B) Hollin Busk Mine
Located on Hollin Busk Lane above Stocksbridge, this was a mixed mine, with both coal and fireclay being extracted from this small shaft mine. Records state that the shaft reached coal at 108 feet and pot clay lower down in the strata at 261 feet. A ventilation shaft was also sunk circa 1900. The whole mine had closed by 1930.
The capped-off winding shaft, brick mounted headgear and wheel hand and adjacent winch survived for many decades became a familiar sight for motorists, before being demolished in early 2017 and the whole site landscaped as an iconic part of the valley's heritage was lost. The owners stated the wheel was being restored so it can be placed at the entrance to the site.
At the time when I came here, I didn’t know the headstock had been demolished. I couldn’t see it anywhere. Then, from the corner of my eye say the old wheel in the corner of yard of a nearby farm. At this stage, the penny dropped. So nothing too impressive by way of photos from this lovely little mine.
The now damaged wheel:
Sitting forlornly in the winter snow:
And some former brick work:
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