Monday, 30 July 2018

The Gleadless Valley

A Google map of the Gleadless Valley showing the Meers Brook

The spring of 2018 was very slow to get going but, having visited Brincliffe Edge quarries and the interior of the church of St. James the Great – both a stone’s throw away from the route of the Sheffield Round Walk – I decided to get out again and explore the Meers Brook, whose many tributaries have cut through the Grenoside Sandstone and the underlying Pennine Lower Coal Measures Formation rocks to form the Gleadless Valley

The geology around the Gleadless Valley

This steep sided valley is best known for its housing estate, which was built from 1955 -1962 and retains large areas of its original ancient woodland and, although I didn’t expect to find any spectacular geology or historic buildings, when I passed through it on my last visit to Norton I thought that it was well worth a visit. 

A view north across the Gleadless Valley

Various styles of housing were designed to suit the contours and the varied slopes, and these range from tower blocks on the edge of the valley, with chalet style and patio houses on the lower slopes – and the Holy Cross Church set in a highly prominent location. 

The Holy Cross Church

In places, the slopes have a gradient of 1 in 4 in places and, with numerous watercourses too, various challenges were presented to the city architect J. L. Womersley and, when wandering around the valley, several culverts and diversions of the natural waterways can be seen. 

A streamside section of siltstone

The tributaries of the Meers Brook have cut deep and narrow courses through predominantly Lower Coal Measures siltstone and shale and the streamside exposures of rock would probably yield fossils to the adventurous research geologist; however, none of these are easily accessible and I wouldn’t really consider the Gleadless Valley suitable for geology field trips. 

A streamside section of shale

That said, once I had continued walking to the old village of Heeley, I encountered a variety of late Georgian and Victorian historic buildings which provide good examples of what I presume to be quite local Pennine Lower Coal Measures Formation sandstone. 

Various historic sandstone buildings in Heeley

Although none of the buildings are particular spectacular, the churchyard of the Grade II Listed Christ Church contains a couple of interesting granite monuments – one a pink granite obelisk with and ornate plinth that commemorates the local steel manufacturer, John Shortridge, and another large ornate monument constructed in grey Aberdeen granite.

Granite memorials at Christ Church graveyard

Wednesday, 25 July 2018

St. James the Great - The Interior

A view east along the nave

When I first visited the church of St. James the Great in Norton, on the last day of March in 2017, it was locked and I only had a brief look at the exterior and the porch. A year later, taking advantage of one of their Farmers Markets, I had the opportunity to take a good look at its interior. 

A view to the west from the chancel

Unexpectedly, I found that all of the very heavy pews in the nave had been moved aside to make way for market stalls, where a wide variety of craft products were available for sale and, one time, a tiny Shetland pony was brought into the church. 

The font

With the church crowded with people, and many of the details obscured or not readily accessible – such as the unusual nine sided Early English font - I wasn’t able to closely study the details, but the principal features were still clearly visible. 

A carved impost to the south arcade

Like very many others that I saw during my extensive tour of mediaeval churches in South Yorkshire and the surrounding counties, in 2016, the Early English north arcade has transitional style columns dating to around the turn of the 13th century but those of the south arcade – which are considered to be 14th century – are octagonal in section. 

A view west along the nave to the lopsided tower arch

The narrow tower arch, which is also Early English, is quite unusual in that it is distinctly lopsided and, like All Saints church in Aston-cum-Aughton, the span of the easternmost arch to the south aisle is much wider than all of the others. 

Derbyshire crinoidal limestone

Although the time or space was not available to take a good look at the building stones, which I had easily distinguished on the exterior, I noticed the use of Derbyshire crinoidal limestone and there is a fine 16th century alabaster chest tomb, dedicated to William Blythe and his wife.

The tomb of William and Saffrey Blythe

The sculptor Sir Francis Chantrey was born in Norton and he is buried in the churchyard. He is commemorated by an obelisk in the village and, inside the church, there is a simple memorial plaque and a full sized  sculpture of him.

A sculpture of Sir Francis Chantrey

Tuesday, 24 July 2018

Brincliffe Edge Rock

An extensive exposure of Brincliffe Edge Rock

When exploring the Porter Valley leg of the Sheffield Round Walk in the spring of 2017, it had originally been my intention to take advantage of one of the leaflets available through the Sheffield Area Geology Trust and visit the old quarries on Brincliffe Edge in Sheffield; however, due to problems with the buses on the day, my plans had to be shelved. 

Brincliffe Edge Rock and dry stone walling on Psalter Lane

As the Chairman and the principal surveyor for the South Yorkshire RIGS Group, I spent a considerable amount of time as a volunteer – with the occasional paid contract – raising the profile of geology in the county. The survey work that I undertook enabled me to get to know the principal building stones in the region much better, which was of benefit to the professional work that I undertake as a stone identification and matching’ specialist – a skill that I first developed when establishing Triton Building Restoration Ltd. in London. 

An exposure of Brincliffe Edge Rock in the Omega Restaurant car park

In August 2005, Planning Policy Statement 9: Biodiversity and Geological Conservation came into force and placed a legal obligation on local authorities to take into account geological sites during the planning process. 

The old quarry face in the Omega Restaurant car park

Doncaster MBC took the bull by the horns and paid for the British Geological Survey to undertake a resurvey of their RIGS for the Local Development Framework, with myself being temporarily employed  to do the survey work and relevant report writing, but the other authorities have never shown any desire to follow suit and, at best, continue to ask volunteers to do their work. 

A sculpture in Quarry Head Lodge depicting  plug and feathers

Although still available to advise on such matters if the need arises, I have since taken a backward step with respect to geological conservation in South Yorkshire and my visit to Brincliffe Edge, in the first week of April this year, was undertaken purely for my own continuing professional development and personal pleasure. 

Rock bolts in the quarry face at Quarry Head Lodge

In the same way that “Rotherham Red” sandstone is the local name given to the locally distinctive variety of Mexborough Rock, Brincliffe Edge Rock, which was once called “Brincliffe Blue”, is a variation of the Greenmoor Rock - whose type locality is in the village of Green Moor, which is found approximately 15 km to the north-west of the Sheffield suburb of Banner Cross. 

A detail of the Brincliffe Edge Rock at Quarry Head Lodge

The old quarries around Brincliffe Hill once produced thousands of tons of grindstones, building stone and gravestones, but they have long since been closed and, except for the car park to the Omega restaurant – now largely overgrown with ivy – have been redeveloped for housing. 

The redeveloped John Gregory Brick Pit on Ecclesall Road

The measures beneath the Brincliffe Edge Rock/Greenmoor Rock – as also seen at Neepsend to the north of Sheffield city centre – were also once widely exploited to make bricks and, when I finished my brief exploration of the old sandstone quarries, I followed the distinct escarpment down to Hunters Bar, where the scar left by the John Gregory Brickworks can still be seen.

A view of a back garden on Ecclesall Road

Saturday, 21 July 2018

A Trip to the Magpie Mine

A general view of the Magpie Mine

After a couple of busy days in February this year, giving a talk to Aston-cum-Aughton History Group and leading the Sheffield U3A Geology Group around Sheffield city centre to look at its building stones, the cold weather and snow put paid to exploring for the next month. 

The Agent's House and Smithy

On a bright but very cold day in March, with a biting wind, the group reconvened at the Magpie Mine in the Peak District National Park, which was the last working lead mine in the Derbyshire ore field until it closed in 1951. 

At the start of the tour

All of the shafts and entrances to the mines are capped and there is no entry to the mine and the main attraction of the site is to wander around the site to appreciate the remains of the engine house, chimneys, miscellaneous buildings and the winding gear, which make it probably the best preserved example of a 19th century lead mine in the UK, for which it merits ancient Scheduled Monument status. 

The winding gear

With no access available to the various buildings, the group was led around the site by Keith Gregory of the Peak District Mines Historical Society, who provided an explanation of its history and told us various tales about of bitter disputes and fights resulting in the “murder” of three miners, and a Widows’ Curse that is said to remain to this day. 

An old winch

As an example of industrial heritage, the Magpie Mine is a fine site and is a very popular tourist attraction; however, as I had realised when exploring various parts of the Sheffield Round Walk the previous year – such as Ecclesall Woods and the Porter Valley – industrial archaeology doesn’t greatly appeal to me and, instead of listening intently to our guide, I just enjoyed being outside in the fresh air and taking a few photographs of the day.

Grindstones made from Carboniferous limestone and Millstone Grit

The Building Stones of Sheffield - Part 4

A detail of a Kilkenny limestone seat on the Moor

By the time that the Sheffield U3A Geology Group had finished looking at the magnificent decorative stones in the interior of Sheffield Town Hall, they had encountered a wide variety of sandstones, limestones, marbles and granites and a few members decided that they had seen enough buildings for one day. 

Sheffield City Hall

Most of the group, however, stayed for the last leg of the walk around Sheffield city centre and, by request, we firstly went to have a quick look at Sheffield City Hall – built out of Darley Dale gritstone and opened in 1932. 

A detail of polished Ashburton marble

Briefly stopping to look at the stone indents used to repair bomb damage from WWII, the wall panelling provides further examples of Hopton Wood limestone and the door surrounds to the entrance shows Ashburton marble – as used in Sheffield Town Hall and Sheffield Central Library – at its best, with the fossil sponges being clearly visible. 

A gritstone lion inside Sheffield City Hall

The gritstone lions were originally sited on the exterior of Sheffield City Hall, but they were for some reason relocated to the offices of Tarmac in Matlock – when I first saw them when undertaking a survey of the RIGS (Regionally Geological Sites) in the Peak District National Park, when living in Bakewell

A general view of Charter Square

We then moved on to Sheffield's most recent public space at Charter Square, where we again encountered Chinese granite for the paving – designed to match the colour and texture of the Spanish and Portuguese granites previously used around Fargate

A Hall Dale sandstone seat in Charter Square

The sandstone used in the seating is the very distinctive Hall Dale sandstone, which in this instance has pink/buff variegation, and the rough boulders – which contain fine beds of coal and some unusual sedimentary structures. 

A rough block of sandstone with fine beds of coal

Although by now, a few members of the Sheffield U3A Geology Group had left to do some shopping or undertake other tasks – which they wouldn’t otherwise be able to do if they had been in the middle of the Peak District or other places – the remainder of the group accompanied me to take a good look at the seating in the Moor

Kilkenny limestone seating on the Moor

I reported on the first phase of this development for the German stone trade magazine StonePlus in 2010, which highlighted the work of Matt Black and Pip Hall, but I hadn’t noticed the seating areas at the top of the Moor before - a celebration of 100 years of stainless steel in Sheffield. 

Dry and wet Kilkenny limestone

Here, like the others at the bottom end of the Moor, the Kilkenny limestone seats have lost their original black colour produced by a fine honed finish – due to the natural degradation of the limestone by carbonic acid in rainwater and the atmosphere, but the fine examples of letter cutting and sandblasting can still be clearly seen.

A detail of sandblasted Kilkenny limestone

Tuesday, 17 July 2018

The Building Stones of Sheffield - Part 3

A bust of Queen Victoria inside Sheffield Town Hall

After a busy morning spent exploring some of Sheffield’s historic buildings and urban landscaping developments, including Sheffield Central Library and the Peace Gardens, the Sheffield U3A Geology Group continued their field trip to Sheffield city centre with a return visit to the library to briefly look at its interior. 

Travertine and Swedish Green marble in Sheffield Central Library

The reception area is notable for the use of beige coloured Italian travertine, a highly porous and open textured limestone that is formed in hot springs, for both the wall panels and the flooring, where it is used in conjunction with green and yellow varieties. 

A pilaster in Sheffield Central Library

In the entrance to the main library, the green variety of travertine forms capitals to pilasters formed of panels of Ashburton ‘marble’, a limestone from Devon that takes a polish and which was once highly favoured for decorating the interiors of grand buildings; however, despite its interior location, the surface has weathered over the years, with the loss of its high polish. 

A view of Sheffield Town Hall from the Peace Gardens

The next leg of the field trip continued with a walk along Surrey Street to Sheffield Town Hall – built in Stoke Hall gritstone from Grindleford - where we stopped briefly to look at the fa├žade above the main entrance, where the fine relief sculpture by Frederick W. Pomeroy depicts the industries of Sheffield. 

A detail of the frieze sculpture by Frederick W. Pomeroy

Inside the main entrance there are more frieze sculptures by Pomeroy and, although the low lighting in this busy thoroughfare makes it difficult to stop and examine the masonry closely, another stone – Ancaster limestone – can be seen here. 

Ancaster limestone in Sheffield Town Hall

Moving into the Main Hall, the group then spent 20 minutes admiring the magnificent decorative stones that have been lavishly used here, which include true marbles and polishable limestones from Connemara and Co. Cork in Ireland, along with others from Devon and Italy, as well as alabaster for the balustrades and Hopton Wood limestone for the wall panels. 

The Main Hall in Sheffield Town Hall

Quite strangely, the sandstone that has been used for elaborately carved stonework both below and above the ‘marble’ panelling was painted in preparation for the last visit of HM Queen Elizabeth II to Sheffield. Stone is a natural material that needs to ‘breathe’ and it is considered bad practice to paint stone in any building – on the outside or the inside - let alone a Grade I Listed building such as Sheffield Town Hall.

A detail of painted sandstone inside Sheffield Town Hall

Saturday, 14 July 2018

The Building Stones of Sheffield - Part 2

Fluvio-glacial cobbles at Sheffield Cathedral

After Sheffield Central Library, the next stop on the U3A Sheffield Geology Group field trip to Sheffield city centre was at the adjoining Tudor Square, where there are several large Crosland Hill sandstone planters designed by the artist Stephen Broadbent.

A large Crosland Hill sandstone planter in Tudor Square

Three hand-made plaster maquettes produced at 1:10 of the size of the final sculptures were laser scanned in Liverpool and each of the 173 individual stones were then carved at their full size by a robot at Johnsons Wellfield in Huddersfield, before being carefully assembled together.

An extract from the Building Stones of Sheffield - by Peter Kennett

Moving on to Fargate via Chapel Walk, the group then had a quick look at some of the various stones that were used during the remodelling of Sheffield’s main shopping street back in 1998. These include Spanish and Portuguese granite setts - laid by a gang of paviour masons from Naples - Caithness flagstone and Red Lazonby sandstone, with the latter showing considerable signs of wear and physical degradation. 

Grotesques on the gate posts in the forecourt of Sheffield Cathedral

Crossing Church Street from Fargate, we stopped at the gate posts on the corner of the cathedral forecourt - to appreciate the elaborately carved grotesques - before examining the coarse locally quarried Rivelin Grit, which has been used for Sheffield Cathedral and the Employment Tribunals Service building on East Parade. 

The statue of James Montgomery

The plinth to the James Montgomery statue in the old churchyard provides an example of Cornish grey granite, which was formed during the Hercynian period of mountain building - like the granites from the Iberian peninsular used on Fargate - but its colour and well formed feldspar crystals give it a very distinctive character. 

Examining the alabaster tomb at the rear of Sheffield Cathedral

To the rear of the cathedral next to Campo Lane, an alabaster tomb that was formerly sited inside the cathedral was moved to its current location in the 1960’s and, being soluble in rainwater, has subsequently disintegrated at an accelerated rate – with fractures in the stone being extensively weathered and its surfaces deeply furrowed. 

Historic buildings on St. Paul's Parade
The morning session was finished with a brief look at St. Paul’s Parade, where Browns brasserie provides a good example of Triassic Red St Bees sandstone, and a good look at the sandstones, granites and volcanic green slate that have been used in the Goodwin Fountain, which forms the centrepiece of the Peace Gardens.

Various stones used in the Goodwin Fountain

Here, as in Fargate, not all of the stones used have fared well after nearly 20 years of wetting and drying and, in winter, freezing and thawing. The Permian Clashach sandstone, in particular, has deteriorated to the extent that much of it really needs to be replaced – something that I suspected after I observed its very variable mineral content, when reporting on the project for Natural Stone Specialist soon after it was finished.

A detail of the Goodwin Fountain in Sheffield Peace Gardens