Farrant, A R. 2008. A walkers' guide to the geology and landscape of western Mendip. (Keyworth, Nottingham: British Geological Survey.) ISBN 978 085272576 4

The guide is available to purchase from the British Geological Survey https://shop.bgs.ac.uk/Shop/Product/BSP_BWMEND

Shipham and Rowberrow

Nestling in the eroded core of the Blackdown Pericline, Shipham [47] [ST 44568 57550] and the neighbouring hamlet of Rowberrow [48] [ST 45276 58287] are situated in an area of great scenic and geological diversity within easy distance of much of western Mendip.

The discovery of zinc ore in the 16th century turned the small settlement at Shipham, noted in the Domesday Book, into a major mining centre. Calamine and smithsonite have been worked from the Triassic Dolomitic Conglomerate. These two common ores of zinc occur as thin veins, and galena (lead ore) may also be present.

The calamine mining industry started in England in the 16th century in the reign of Elizabeth I. The main use of calamine was as an alloy, mixed with copper to form brass, but it was also sold to pharmacists for its medicinal properties. Today calamine lotion is still available as a soothing and mild antiseptic lotion for use on irritating skin conditions.

At first calamine was mainly exported, but by the end of the 16th century the brass industry was well established in Britain. By the 18th century the calamine industry was at its height and Mendip calamine was considered to be the best in England. The biggest brass foundries were in nearby Bristol, but Mendip calamine was also transported to others at Birmingham. The ore was now also used to produce metallic zinc (spelter), with William Champion of Bristol being the first to patent the process in 1738. However, by the early 19th century the mining had almost ceased and in 1839 Sir Henry de la Beche (the first director of the British Geological Survey) noted that calamine working on Mendip had been largely discontinued for some time.

Mining gave employment to a large number of people in Shipham and Rowberrow. There were reported to be more than 100 mines around the Shipham area and four calamine ovens were built where the calamine was baked before being powdered and sold on. The last of these remained standing behind Court House until the 1980s. Many buildings sprang up on the common land to the east of the centre of Shipham where the miners laid their claims.

Although mining targeted calamine, galena was also commonly found and extracted for sale. The mines were mainly shallow as the ore formed within small veins in the Dolomitic Conglomerate. This lay close to the surface and extraction took place in numerous small mines and pits. The mines were generally only 30–40 m deep and were usually worked by hand with only the aid of a hand-turned windlass and a bucket. Some Cornish beam engines were employed later on in the deeper workings. The last mine to remain open in Shipham was the deepest, and was situated in the centre of the village. When mining in the Shipham area ceased many miners were forced to walk over Blackdown for work in the then thriving Charterhouse mines.

Many people living in Shipham were reliant on mining for income and life could be tough and squalid. The miners of Shipham were notorious for being rough, and it was reported that no constable would arrest them for fear of disappearing down one of the many mine shafts. Hannah More, the well-known philanthropic writer, was appalled by the poverty in the area and in 1790, with the help of William Wilberforce, the well-known social reformer, was instrumental in setting up both a Sunday school and a day school, as well as the first of the ‘female clubs’ on Mendip.

Shipham is a now a thriving community. However, around the village there is still plenty of evidence to bear testament to its mining history with street names such as Hind Pits, the Miners’ Arms Public House and a Miners’ Cottage listed along Hollow Road. To the south-east of the village the West Mendip Way passes through an area of gruffy ground [49] [ST 44831 57270], a local name which refers to hummocky ground formed by the remains of old mine workings and waste. Hollows where the numerous shafts entered the ground can still be clearly seen here. From this area of gruffy ground on a clear day there is a good view over to Weston-super-Mare and the coast.

Several mines are still accessible to cavers, notably Singing River Mine and Star Mine. The legacy of mining also remains in the form of heavy metal contamination of the soil. Shipham has the highest levels of cadmium in the soil anywhere in the UK. Cadmium is a toxic metal associated with old zinc mine workings. These have been disturbed by recent development and agriculture. Many houses and gardens are on the old mine workings. The health of Shipham residents was extensively investigated in 1979**See for details: www.mod.uk/publications/zinc_cadmium/summary.htm. Even though the cadmium content of the soil was high, the dietary intake of cadmium by the villagers had no measurable effect on health. As the cadmium in the soil is tightly bound up in minerals, it is not readily available for uptake by plants and hence does not enter the food chain.

To the north of Shipham in Rowberrow [48] [ST 45276 58287] the numerous cottages built during the influx of miners have mostly disappeared, although the influence of the miners is still apparent in the hummocky nature of much of the land in the area. The majority of the miners’ dwellings were located along what is now School Lane and in the valley known as Rowberrow Bottom.

The upper reaches of this delightful valley [50] [ST 45805 57252] are excavated in the relatively impermeable Portishead Formation sandstone. A small stream flows down here, but disappears underground at several points into the Dolomitic Conglomerate near Rowberrow, to emerge at Banwell Risings several days later. From the area around Shipham and Rowberrow a large number of footpaths and cycle ways can be accessed, which lead through Rowberrow Forest and over the sandstone heath of Blackdown to the east, towards Shute Shelve to the south-west and towards Dolebury Warren and Churchill in the north.

South of Shipham is Long Bottom [51] [ST 45054 56692]. This straight valley is a good example of differential erosion. Here the softer Avon Group mudstone has been preferentially eroded, leaving the harder Carboniferous Limestone forming a craggy scarp to the south.

Figures

(Figure 57) A stone wall in Rowberrow made up of grey Carboniferous Limestone, dark red sandstones of the Portishead Formation, and thin slabs of pinkish Triassic Dolomitic Conglomerate.

(Figure 58) North–south cross-section from Shipham Gorge to Churchill Gate. Mineral veins bearing lead and zinc ore penetrate up though the Portishead Formation and into the Dolomitic Conglomerate. Near-surface weathering has altered and enriched the primary ores into the workable ore deposits exploited by miners in the 17th and 18th centuries.

(Figure 59) Aerial phototograph of the Shipham and Rowberrow area.

(Figure 60) An area of ‘gruffy ground’, a local name for areas of old mine workings, trial pits, spoil heaps and mine shafts on the south-east side of Shipham.

(Figure 61) Rowberrow Bottom.

(Figure 62) Rowberrow Bottom. The stream here is flowing on the impermeable sandstones of the Portishead Formation.

(Figure 63) Old limekiln, Rowberrow Bottom.