From Howard Road to Mushroom Lane

 

A specimen of Greenmoor Rock from Mushroom Lane

During my exploration of Crookes and Walkley, in the north-western part of the city of Sheffield, I had traversed the Crawshaw Sandstone, the Loxley Edge Rock and the Rough Rock, in addition to the mudstones and siltstones of the intervening Pennine Lower Coal Measures Formation strata.

 

The geology around Walkley and Crookesmoor

I had seen several examples of the Crawshaw Sandstone in the larger historic buildings, with a distinctive uniform pale buff colour and well defined horizontal bedding. Although the 1855 Ordnance Survey map shows a couple of quarries on the Loxley Edge Rock in Lower Walkley, this area had been covered in housing by the time of the 1894 edition and the Bole Hill Quarries had grown substantially.

 

A sandstone built terrace in Walkley

 

On my walks, I didn’t take any time to look closely at the very many terraced houses and shops that I passed by, but I did notice variations in the colour, iron content and the bed height of the walling stone – all of which would be expected in any named rock formation in the Pennine Coal Measures Group.

 

St. Joseph's Chapel

Taking a diversion off Howard Road, I had a quick look at St. Joseph’s Roman Catholic chapel, dated 1870, which was once part of St. Joseph’s Home – an institution that went through various phases of use and had close links to St. Vincent’s church on Solly Street, in central Sheffield.

 

St. Joseph's Chapel

With limited access to this area and with the late afternoon sunshine in February making it very difficult to take good photographs, I didn’t see anything particularly noteworthy in the stonework and retraced my steps to Howard Road.

 

A fracture in the boundary wall on Fulton Road

 

On the way, however, I was very interested in the retaining wall on Fulton Road, which formed the boundary to  St. Joseph's Home. Apart from showing distinct signs of structural movement, which had required the insertion of tie rods and anchor plates, it provides an example of another rock formation – the Greenmoor Rock.

 

Tie rods and anchor plates on Fulton Road

 

Known in Sheffield as the Brincliffe Edge Rock, the best quality laminated sandstone gained a national reputation for the paving stones and monuments that were made from this very durable stone – with it also being widely used locally for kerbs and road setts; however, the siltstone grade rock is only suitable for basic walling and boundary walls, as seen here.

 

The former St. Joseph's School

Arriving back on Howard Road, I looked down to the former St. Joseph’s School – which was built on land owned by St. Joseph’s Home by an unknown architect; however, the statue of St. Michael slaying Satan is apparently by the York sculptor - George Walker Milburn.

 

The statue of St. Michael

 

Walking quickly down to Crookesmoor, I stopped to take a photograph of the monumental Crookes Valley Methodist Church without having a good look at the stonework, which was bathed in the late afternoon sunshine, before carrying on down to Crookes Valley Park.

 

Crookes Valley Methodist Church

The park is set on siltstone and mudstone, which forms a vale between the dip slope of the Loxley Edge Rock to the north and an escarpment of Greenmoor Rock to the south, which here dips 25 degrees to the south-east. Making my way up this escarpment, I then stopped at a very small outcrop beneath the boundary wall at the top of Mushroom Lane.

 

A small outcrop of Greenmoor Rock on Mushroom Lane

Using my new Estwing hammer, I obtained a sample of the Greenmoor Rock, which here is a grey/green very fine grained silty sandstone, with one surface covered in dark brown iron oxides/hydroxides that often form along the joint planes.

A specimen of Greenmoor Rock