Reasons for Designation
Approximately 10,000 lead industry sites are estimated to survive in England,
spanning nearly three millennia of mining history from the later Bronze Age
(c.1000 BC) until the present day, though before the Roman period it is likely
to have been on a small scale. Two hundred and fifty one lead industry sites,
representing approximately 2.5% of the estimated national archaeological
resource for the industry, have been identified as being of national
importance. This selection of nationally important monuments, compiled and
assessed through a comprehensive survey of the lead industry, is designed to
represent the industry's chronological depth, technological breadth and
regional diversity.
The ore works were an essential part of a lead mining site, where the mixture
of ore and waste rock extracted from the ground were separated (`dressed') to
form a smeltable concentrate. The range of processes used can be summarised
as: picking out of clean lumps of ore and waste; breaking down of lumps to
smaller size (either by manual hammering or by mechanical crushing); sorting
of broken material by size; separation of gravel sized material by shaking on
a sieve in a tub of water (`jigging'); and separation of finer material by
washing away the lighter waste in a current of water (`buddling').
The field remains of ore works include the remains of crushing devices,
separating structures and tanks, tips of distinctive waste from the various
processes, together with associated water supply and power installations, such
as wheel pits and, more rarely, steam engine houses.
Simple ore dressing devices had been developed by the 16th century, but the
large majority of separate ore works sites date from the 18th and 19th
centuries, during which period the technology used evolved rapidly.
Ore works represent an essential stage in the production of metallic lead, an
industry in which Britain was a world leader in the 18th and 19th centuries.
Sites are common in all lead mining areas and a sample of the best preserved
sites (covering the regional, chronological, and typological variety of the
class) will merit protection.
The remains of Watt's Grove Rake lead mines 520m north of Sweetknoll are
particularly well preserved and include a diverse range of components relating
to the mining of this vein. Rake workings of such veins are now rare, and this
example is one of the best preserved examples in the Peak District. The
standing, earthwork, buried and rock cut remains provide evidence for both the
historical and technological development of what was once a far more
extensive, multi-period mining landscape. They incorporate a wide range of
mining and processing features, which enable the development of the mine
working and its chronological range to be reconstructed. The large rake,
shafts, hillocks and other extraction features provide evidence for methods of
extraction whilst other processing areas will contain deposits showing the
effectiveness of these techniques. The mining remains also provide an insight
into the Derbyshire Barmote Court system of mining and the constraints this
imposed on the miners of the area.
Details
The monument includes the earthwork, buried, standing and rock cut remains of
Watt's Grove Rake. The monument is linear in shape and runs east to west for
approximately 1.45km along the south side of Eldon Hill, on the western slopes
of Conies Dale. The continuous line of workings along the vein includes
intermediate concentrations of areas of activity associated with Watt's Grove
and Jowle, or Joule Grove mines. Linear rake mining of lead was typical in the
Peak District.
It is unknown when the rake was first worked, but Dirtlow Rake, from which
Watt's Grove Rake branches, is thought to have been worked in the medieval
period. The working of Jowle Grove is documented from at least 1789 when it
was recorded that Samuel Fox `can drive a level from Jowl Grove to Portaway
Mine, seven feet and two feet in size and have all the ore got in driving the
said level'. Mining had ceased by the late 19th century when the Ordnance
Survey Map of 1880 describes the rake as `old'. Watt's Plantation, which
follows the line of the rake, was planted between 1880 and 1922.
The mines would have been worked under the jurisdiction of the Barmote Courts,
the legal administrative unit governing Derbyshire lead mining. The Derbyshire
system of mining was largely based on local mining customs and consisted of
individual groups of miners or small mining companies working relatively short
lengths of the vein.
The monument survives as a series of earthwork, buried and standing remains
which include belland yard walls (substantial walls built around dressing
floors in order to prevent cattle straying and eating grass contaminated by
lead), ruined coes (stone built shelters or sheds), open cuts (veins worked
open to daylight), a bouse team (a bin into which ore was stored before
processing), water channels, washing floors, leats, buddling dam (an earth dam
into which was placed the dirt and sludge resulting from the process of
separating small sized ore from adhering dirt (buddling)), crushing floor (an
area where ore was crushed ready for further treatment), gin circles (remains
of horse powered winding apparatus), climbing shafts, water storage pond and
engine shaft.
The remains of Jowle Grove mine are located at the eastern end of the
monument, in Watt's Plantation, where a group of features mark a concentrated
area of activity. Included within this area is a crushing floor paved with
limestone slabs which is, unusually, protected by a low retaining wall. The
wall may have acted as a very small belland yard wall. The well preserved
remains of an engine shaft and gin circle are also visible although the shaft
is now covered with timber baulks. A stone built double coe, now filled with
limestone rubble, is thought to house a climbing shaft which provided access
to the working places in the mine.
Another concentrated area of activity lies immediately to the west of Jowle
Grove but still within Watt's Plantation. This is known as Watt's Grove Mine.
The remains of a gin circle and a funnel shaped water storage pond are easily
visible. The gin circle has partly collapsed into an open cut but is still
clearly discernable on the ground. Part of a small area, in the southern
section of the plantation, has been disturbed but the remains of a shaft and
the hillocks survive and form an important element in the otherwise
undisturbed linearity of the rake.
The rake continues in a westerly direction and is marked by up to three
parallel lines of large hillocks made up of limestone deads (waste rock which
contain no ore or insufficient quantities to warrant extraction). An area
of the rake, centred at national grid reference SK11808065 is enclosed by a
belland yard wall which contains the remains of dressing floors, a buddle dam,
washing ponds, leats, a water storage pond, a climbing shaft and a main shaft
although the latter is now covered in concrete. The water storage pond is
known to be at least five feet deep. Also within the enclosed section two of
the open cuts contain walls of deads which are built up between the vein walls
on bunnings (stagings built across a worked out vein onto which the deads were
placed). The dry stone walls provided a convenient way to store waste rock
which saved the trouble and expense involved in drawing it to the surface.
To the west of the belland yard wall the rake continues a further 760m and
ranges in width from 60m to 20m. This section of the rake lies within a
plantation and is defined along most of its length by field boundary walls.
Along this section there are a lot of examples of individual shafts joined
together by well preserved hillocks. These remains demonstrate the vertical
working of the rake by mines with access to several meers of the vein at a
time (a meer is a linear measurement equivalent to 32 yards). The extraction
techniques demonstrated by these existing surface remains illustrate the way
that the legal framework governed the working of the lead mines in Derbyshire.
All modern fencing is excluded from the scheduling although the ground beneath
these is included.
MAP EXTRACT
The site of the monument is shown on the attached map extract.
