Summary
The monument includes the earthworks and buried remains associated with an area of calamine working which was worked probably in the C17 and C18, though it possibly has earlier origins.
Reasons for Designation
The earthworks and buried remains of an area of C17 and C18, and possibly earlier, calamine working situated to the south of Glovers Field, Shipham are scheduled for the following principal reasons:
* Survival: as a well-preserved and rare survival of a calamine mining site which displays surface and below-ground evidence of mining and ore-processing techniques;
* Diversity: for its diverse range of features, including outcropping works, densely-packed shallow pits and simple bell pits which represent various methods of extraction, together with areas of ore processing;
* Potential: it will enhance our knowledge and understanding of the technological development of mine working and the chronological depth of the site, as well as the place it held in the wider economic landscape;
* Group value: although located further afield, the site has group value with the Grade II-listed calcining kiln to the west;
* Landscape: the site contributes strongly to the character of the landscape, providing visible evidence of the historic impact of calamine mining on the local area.
History
The manufacture of brass was established in Britain in the late C16. Documentary records indicate that calamine (the principal ore of zinc) which was used in brass production was being worked in the Shipham area by 1665. Not only was it used in the British brass industry, but some was exported from the mines in the Mendip Hills to the Low Countries; it was also used for medicinal purposes, including the treatment of eye ailments. By the start of the C18, the demand for brass increased and Mendip calamine, considered to be the best in the country, was in great demand for the brass foundries in Bristol. Unrefined zinc ore calamine was used initially in brass production, but this made it difficult to accurately determine the desired proportion of copper to zinc needed, and the finished product often contained a significant amount of slag. Calamine brass was slowly phased out as zinc smelting techniques were developed which produced metallic zinc more suitable for brass production. The Shipham area became the main centre of calamine mining for the Bristol brass industry, which in turn dominated national production, and mining peaked in the middle of the C18. In the late C18 it was reported that the entire populations of the villages of Shipham and nearby Rowberrow (to the north) were engaged in mining, with over a hundred mines in Shipham alone, many of them ‘in the street, in the yards and some in the very houses’ (Gough, see SOURCES). A shanty town also developed around the outskirts of Shipham to accommodate the miners. Further technological developments in brass production soon followed, with Bristol brass-maker William Champion pioneering the large-scale commercial production of metallic zinc from calamine in the 1730s. By the mid-C19, however, the exhaustion of available ores close to the surface, the gradual decline of the calamine-brass industry and competition from cheap imports from abroad meant that mining in and around Shipham was no longer economical. Some sporadic mining occurred up until the 1870s, but most operations had ceased by then.
Aerial photographs taken in 1946 indicate that the calamine workings around Shipham were extensive, with the lode running north-west to south-east in two locations: the Shipham Run to the south and south-east of Shipham and the Rowberrow Run situated between Shipham and Rowberrow. However, since the mid-C20 the expansion of Shipham and farming activities have led to the loss of some areas of calamine mining, including those associated with the Rowberrow Run. The former mine workings to the south-east of Shipham are characterised by areas of 'gruffy' ground, a local name for uneven hummocky landscape created by calamine mining. Here the earthworks form quite a distinctive pattern. In their simplest form the workings took calamine from outcrops close to the surface, digging either closely-spaced shallow pits or long grooves which did not connect underground. Once shallow deposits had been exhausted, deeper shafts were excavated to exploit the ore at greater depths. Although stationary steam engines were employed to haul ore to the surface during the C19 at some Shipham mines, the majority used only a windlass and bucket. The ore was then washed and sorted, and sometimes calcined (roasted) in an oven, before being transported to Bristol.
Details
PRINCIPAL ELEMENTS
The monument includes a number of earthworks and buried remains associated with an area of calamine working which was worked probably in the C17 and C18, though it possibly has earlier origins. The varied earthworks include shallow pits, trenches and shaft mounds and related calamine-mining features on the south-east edge of the village. They are situated on ground which rises gently to the east and south-east and are believed to date from the C17 and the C18, although evidence for post-medieval mining may be present.
DESCRIPTION
The eastern part of the site retains a dense concentration of mine working characterised by intensive pitting that appears irregular in form. The shallow pits or scoops are amorphous, ranging in size from 1m to 4m across, and the spoil heaps are not clearly defined, generally taking the form of irregular mounds and banks which vary widely in their dimensions, and slump into one another. These earthworks are indicative of the early manual extraction of calamine ore, with closely-spaced pits to optimise output. To the south-west is a long, narrow trench which has linear spoil dumps to either side. It has a south-west to north-east alignment and is considered to be the opencast working of a calamine vein located relatively close to the surface.
Other parts of the site, to the north and west, are dominated by the remains of larger-scale extraction which are characteristically later in date. They comprise large, discrete features in the form of circular shaft mounds with pronounced collars of spoil up to 1m high. In this later process a shaft was dug to gain access to deeper veins; these shafts were commonly known as bell pits as the calamine was extracted to a maximum safe width around the base of the shaft resulting in the bell shape from which the pits are named. The spoil from the shaft was mounded around the top of the shaft producing, over time, a conical hollow resulting from the collapse of the shaft or its infill after workings had ceased. Generally downslope of, and adjacent to, a number of the bell pits are rectangular features which are defined by low earthwork banks. These have been interpreted as ore processing areas, although it is possible that some formerly contained pumping equipment.
EXCLUSIONS
All fences, gates, stiles and boundary walls are excluded from the scheduling, however the ground beneath these features is included.
EXTENT OF SCHEDULING
The area of protection aims to include the well-preserved earthworks and buried deposits relating to the calamine mining to the south of Glovers Field. Further mining remains lie outside the area of protection, but the main concentration of surface remains are encompassed. The northern extent of the monument is, therefore, defined by the field boundary parallel with the gardens of the properties on the south side of Glovers Field; to the north-east, it is formed by the boundaries of 7 and 8 Deer Leap. To the east and south-east, the boundary has been drawn to include the known extent of surviving earthworks and partly follows the route of the West Mendip Way. The earthworks beyond the eastern boundary have been damaged or destroyed through levelling and dumping. The monument boundary in the southern and western parts of the site follow a field boundary and the course of a former field boundary respectively to include the linear open-cast trench and an area which contains a concentration of bell pits. Several further bell pits are evident to the west of the monument but these are more isolated and more widely-dispersed survivals and are not, therefore, included in the area of protection.
