Summary

Tugmore Shaw iron mine pits, 320m south-west of Autumn Cottage

Source: Historic England

Details

This record was the subject of a minor enhancement on 18 June 2014. The record has been generated from an "old county number" (OCN) scheduling record. These are monuments that were not reviewed under the Monuments Protection Programme and are some of our oldest designation records.

The monument includes iron ore mine pits surviving as earthworks and below-ground archaeological remains. It is situated on a ridge overlooking a stream valley, in an area of woodland known as ‘Tugmore Shaw’, north-west of Hartfield on the Weald. Iron ore was extracted from the site, probably in the post-medieval period, through bell-pits and open-cast mines.

The site includes up-cast remains and preserved working faces, a banked trackway and a boundary bank. There are a large number of pits of all sizes ranging from about 3m to 37m in diameter and up to 10m deep. The smaller pits are visible as saucer-shaped craters or depressions. The larger pits are water-filled and have the appearance of ponds. A banked trackway has been identified running through the site from the north-east to the south-west. An old boundary bank contains considerable quantities of iron slag, which is thought to derive from possible ore roasting or calcining sites among and adjacent to the pits.

The fields to the south of the wood are traditionally known as ‘Great Mine Pits’ and ‘Little Minepits’. The site was surveyed by the Wealden Iron Research Group (WIRG) between 1981 and 1982.

Further archaeological remains survive within the vicinity of this monument, such as a bloomery, but are not included because they have not been formally assessed.

Source: Historic England

Reasons for Scheduling

Iron has been produced in England from at least 500 BC. The iron industry, spurred on by a succession of technological developments, has played a major part in the history of the country, its production and overall importance peaking with the Industrial Revolution. Iron ores occur in a variety of forms across England, giving rise to several different extraction techniques, including open casting, seam-based mining similar to coal mining, and underground quarrying, and resulting in a range of different structures and features at extraction sites. Ore was originally smelted into iron in small, relatively low-temperature furnaces known as bloomeries. These were replaced from the 16th century by blast furnaces which were larger and operated at a higher temperature to produce molten metal for cast iron. Cast iron is brittle, and to convert it into malleable wrought iron or steel it needs to be remelted. This was originally conducted in an open hearth in a finery forge, but technological developments, especially with steel production, gave rise to more sophisticated types of furnaces.

Iron ore occurs in two main chemical forms, as a carbonate and as an oxide. The carbonate ores require calcining (roasting) to drive off carbon dioxide, converting the ore into an oxide before it can be smelted to produce iron or steel. Calcining also improves the ore for smelting by driving off water and other volatile substances, and by breaking the ore into smaller fragments. The earliest and simplest method of calcining was to pile ore and fuel into a heap known as a clamp, and then to set light to it. The sites of clamps can sometimes be recognised by deposits of gritty red or purple calcine dust, also known as fines. Although clamps were used into the 20th century in some areas, they were generally replaced with calcining kilns from the 17th century, as these were found to require less fuel. Calcining frequently took place close to where the ore was smelted, and sometimes actually at the mine, especially where transportation costs were a major factor.

Tugmore Shaw iron mine pits survive well they are an example of early mine pits that have not been back-filled. As such it is a good example of its type and provides evidence for a range of extraction techniques. There is evidence for a trackway and for possible ore roasting or calcining on the site which is of particular interest and enhances its significance.

Source: Historic England

Sources

Other
Crossley, D. 1991. English Heritage Monuments Protection Programme. Industrial Monuments: The Iron and Steel Industries. Step 3 report. Version O (Site Assessment 71). ,
Sources: NMR TQ43NE5. PastScape 406930,

Source: Historic England