| Summary : The remains of the Ash Holm Alum Quarry and works (also known as Holms or Rock Holes) lie mostly on the south side of East Row Beck valley in Mulgrave Woods, although there is also evidence for the dumping of red burned shale north of the beck. The works was opened in 1612 and closed in the 1730s when the Kettleness and Sandsend works began production. The quarry comprises a massive scoop cut into the south face of the river valley, with a high, near vertical southern face above a series of terraces which represent working platforms for extracting the grey alum shale. Much of the floor of the quarry is obscured by spoil, principally burned shale discarded after the process known as steeping (a number of waterlogged depressions adjacent to the quarry face may be the remains of the final-phase steeping pits). Earlier calcining places and steeping pits probably lie buried beneath spoil further north, as quarrying would have started close to the river and moved south, with processing facilities for the shale repositioned each time the quarry face moved in order to minimise distances over which the mined shale had to be transported. The alum makers would also have exploited the natural slope of the land to facilitate easy movement of both shale and alum liquor, and deposits of red shales visible on the north side of the beck suggest that many of the structures associated with steeping and the later stages of processing, including the alum house, were initially sited here. The site is scheduled, except for the area of red shales north of the beck. From 1811 the site was used for cement stone quarrying. |
More information : The monument includes the remains of the alum quarries and associated features in the south face of East Row Beck valley in Mulgrave Woods, 350m south east of Mulgrave Castle. As well as the quarries, the monument also includes structures used for the initial processing and transportation of the alum. The Ash Holm works were established by 1609 and closed in the 1730s, partly because the inland location and falling prices made the works unprofitable and also because Mulgrave Woods was being landscaped as a formal park. The quarry includes a massive scoop cut into the south face of the river valley. At the south face there is a near vertical quarry face above a series of terraces which represent the working platforms for extracting the alum shale. Below the face is a steep scarp slope partly obscuring the terraces with large stones and boulders strewn around. To the east and west sides of the scoop the sides slope to the central quarry floor. At the base of the quarry face, extending northward, is a series of spoil tips. These tips are of both quarry waste and spent shale, discarded after the process known as steeping. There are a number of waterlogged ponds adjacent to the tips which are interpreted as the remains of steeping pits. Further north on lower ground are more spoil tips and earthworks from features associated with the later stages of processing. The alum used the natural slope of the land in order to have easy movement of alum liquor from one process to another. There is a clearly defined tramway extending northward from the area of processing works. Further remains of structures such as the alum house as well as workshops, a laboratory, offices and stores are thought to survive below ground level.
The site was also exploited for cement stone mining, using calcerous nodules mined from the alum shales. The mining for cement stone has partly obscured the remains of the alum works. The production of cement may also have stopped when the Mulgrave Woods was formally emparked in the 18th century. The footbridge is excluded from the scheduling, although the ground beneath it is included.
Scheduled, RSM no 31333. (1)
NZ 8426 1150 (FCE). The site was briefly perambulated by Marcus Jecock and Alastair Oswald as part of the EH: Alum Industry Project, accompanied by David Pybus, a local expert on the alum industry, on 27 November 2006. The works seems largely as described in the scheduling documentation (authority 1), except that the alleged tramway was not seen and from what is known of alum sites elsewhere is more likely to be a barrow run or finger tip anyway; it is also improbable that the works closed because of the landscaping of the park, as the latter did not happen until later in the century; furthermore, the cementstone mining is more likely to date to the period 1811-1935, which is the period of operation of the nearby Mulgrave Cement Works (NZ 81 SE 30) on the edge of Sandsend village.
Several additional observations can be made. A couple of deep, semi-circular cuts in the shale immediately adjacent to the south side of the beck may be two of the earliest calcining places constructed on site, whilst another in the south-west corner is possibly the last to be used immediately before the works closed (new calcining places would have been created as the active quarry face moved south in order to minimise distances over which the mined shale had to be moved for calcining). Furthermore, in addition to the red (ie calcined or burned) shale dumped within the quarry floor, a large area of dumping is also visible opposite the quarry on the north side of the beck outside the currently scheduled area which ends at the beck. The most likely explanation for this northern dumping is that the area was also quarried when the works was first established - a vertical cut is visible in the shale extending almost to river level in the north bank of the beck c 20m upstream of the westernmost of the two footbridges at Ash Holm - perhaps not so much to win shale for alum production, but simply in order to create an area in which the alum house and earliest steeping pits could be established at a lower level than the main quarry: burned shale from the suggested early calcining places on the south side of the beck could then be barrowed on the level (rather than uphill) across the beck to the pits and alum house. Once the quarry face had moved a distance to the south away from the beck, new steeping pits would no doubt have been established within the quarry floor, although it is perhaps less likely that the alum house was relocated straightaway, if at all. The northern area was then evidently used to dispose of burned shale, in which case it is possible that the earliest pits and alum house lie buried, just outside the currently scheduled area. According to information in the National Archives at Kew (2a), an alum house certainly existed at Ash Holm in 1624.
The site is now wooded and in most places heavily overgrown, although the area at the foot of the quarry face has recently been cleared of scrub trees to create a grassy open area for pheasant shooting. (2)
The Alum works may have been abandoned during the early 18th century due to the creation of the landscape park. The area is planted with conifers although significant remains may survive beneath the surface. (3) |