Details

The monument is situated within unenclosed moorland, on either side of Ashfold
Side Beck, 2km west of Merryfield Hall. Falling within nine areas of
protection, the monument includes the ruins, earthworks and buried remains of
the Upper and Lower Stony Grooves and Merryfield Hole lead mines and part of
an associated water supply system.
The Ashfold Side Beck marks the ancient boundary between two mineral
royalties, and this is reflected in the early development of the lead mines.
Documentary sources indicate that the Merryfield Hole area, on the north side
of the Beck, was known as Hirefeldberg mine, and was mined by Bylands Abbey
from the 13th century into the 16th century. Mining of this period is believed
to have taken the form of surface extraction which is represented by
distinctive hushed opencut workings at Merryfield Hole. The mines continued to
be worked on an intermittent basis until closure in the later 19th century. In
the last years of mining at Merryfield Hole, the mine was combined with Stony
Grooves mine and worked as a single venture.
The Stony Grooves mines, on the south side of the Beck, are first mentioned
in 1705 but were well established by that date. This period of mining involved
the sinking of regularly spaced shallow shafts and small opencuts along the
uppermost part of the vein. Advances in mining technology led to the
concentration of the mines around single shaftheads in the late 18th and early
19th centuries, and to the introduction of steam power in the later 19th
century. The leases were worked in tandem by a series of independent
partnerships during the 19th century, until the increasing cost of draining
the lower levels led to final closure in 1889.
In the western part of the site, situated on the south side of the Beck and
within a separate area of protection, are the ruins and earthwork remains of
the Upper Stony Grooves mines. Three phases of mining are represented here,
from opencut working directly on the vein, to regularly spaced shallow shafts
sunk along the uppermost part of the vein, and the later concentration of the
mine based on a single shafthead. The opencuts consist of shallow surface
workings, spoil tips, and include the remains of small huts. These workings
are relatively primitive and are likely to represent the earliest workings of
the Stony Grooves mines. Lower parts of the vein were then worked from a
series of small shallow shafts, including small areas of opencutting, running
from the west end of Upper Stony Grooves eastwards to the Lower Stony Grooves
mine. These six shaftheads are each included in the scheduling as separate
areas of protection orientated in a line from north west to south east.
The final phase of mining at the Upper site saw the concentration of workings
based around a single shafthead. Remains of machine settings and a bob-pit (a
pit housing a balance-bob to counter the great weight of pump rods) on the
south side of the shaft indicate the former location of a small steam engine.
Water for the boiler is likely to have been supplied from a small dam to the
south west which is also included in the scheduling. The well preserved
remains of four bouse teams (wash kilns) lie immediately to the east and form
one side of an enclosed yard area. The bouse teams were used to separate the
ore between partnerships prior to dressing.
The Lower Stony Grooves mine, situated on the south side of the Beck, at the
eastern end of the site and within a separate area of protection, consists
largely of a 19th century dressing floor, centralised shafthead arrangement,
and a large dam. The design of the dressing floors is typical of the
increasing concern for efficiency within the 19th century lead industry,
though the high standard of its masonry construction is believed to be
relatively uncommon. The first floor has two bouse teams, of identical design
to those at Upper Stony Grooves, which received ore from the adjacent main
shafthead. The second floor includes the remains of a waterwheel used for
winding the shaft, and an adjacent area which housed a trommel (a set of
rotating sieves for dividing the ore by size). The third floor included a
central waterwheel for powering a crusher and a set of jiggers (mechanically
operated sieving devices). The fourth and lowest floor was used to collect
fines material (very small pieces of ore) and includes the well preserved
remains of a centre head buddle, the only example known to have been built in
the Greenhow mining district.
Water for the dressing process and to power waterwheels was supplied from a
pond, retained by a low earth bank with external drystone walls, situated on
the south west side of the dressing floor. The water is likely to have been
topped up from a more substantial reservoir, the dam of which is also included
in the scheduling within a separate area of protection, situated 150m to the
south on the Cranberry Gill. This dam consists of an earthen core with a
substantial external stone wall. Merryfield Hole mine is situated on the north
side of the Beck opposite the Lower Stony Grooves mine. The Hole itself is a
hushed openpit (a large irregular excavation created at least in part by
controlled torrents of water). Water was fed to the site from small dams at
the head of the openpit. The central part of the site includes the ruins of a
small late 19th century boiler house, chimney, and a small engine plinth
situated above the principal shafthead of the later mine. A large waterwheel
pit 50m to the south, now surviving as ruins, is thought to have powered the
dressing floors for the mine. The floors will survive as buried deposits to
the west and north west.
All modern fence posts are excluded from the scheduling, although the ground
beneath is included.

MAP EXTRACT
The site of the monument is shown on the attached map extract.

Source: Historic England

Reasons for Scheduling

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.
Nucleated lead mines are a prominent type of field monument produced by lead
mining. They consist of a range of features grouped around the adits and/or
shafts of a mine. The simplest examples contain merely a shaft or adit with
associated spoil tip, but more complex and (in general) later examples may
include remains of engine houses for pumping and/or winding from shafts,
housing, lodging shops and offices, powder houses for storing gunpowder, power
transmission features such as wheel pits, dams and leats. The majority of
nucleated lead mines also included ore works, where the mixture of ore and
waste rock extracted from the ground was 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
sizes (either by manual hammering or 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 vary widely and 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.
The majority of nucleated lead mines with ore works are of 18th to 20th
century date, earlier mining being normally by rake or hush and including
scattered ore dressing features (a 'hush' is a gully or ravine partly
excavated by use of a controlled torrent of water to reveal or exploit a vein
of mineral ore). Nucleated lead mines often illustrate the great advances in
industrial technology associated with the period known as the Industrial
Revolution and, sometimes, also inform an understanding of the great changes
in social conditions which accompanied it. Because of the greatly increased
scale of working associated with nucleated mining such features can be a major
component of many upland landscapes. It is estimated that several thousand
sites exist, the majority being small mines of limited importance, although
the important early remains of many larger mines have often been greatly
modified or destroyed by continued working or by modern reworking. A sample of
the better preserved sites, illustrating the regional, chronological and
technological range of the class, is considered to merit protection.

The lead mining remains at Stony Grooves and Merryfield Hole survive
particularly well and include an important documented survival of medieval
openworking. They provide evidence for the transition from mining based on
regularly spaced simple shafts sunk directly on to the vein to the later
capital intensive mines based on centralised shaftheads and deep levels. The
design of the dressing floors, at Lower Stony Grooves in particular, reflect
the trend towards efficiency and capacity in the 19th century industry, though
the high quality of the masonry construction is believed to be uncommon. They
also include the well preserved remains of bouse teams (wash kilns), the
design of which is uncommon nationally, and allowed the ore to be washed
within the individual ore bins prior to dressing. The dressing floors also
include a round buddle considered to be the only known example of its type in
the Greenhow mining district. In addition, important buried features will
survive, particularly at Upper Stony Grooves and Merryfield Hole, providing
information on the early dressing activities that occurred in these areas.

Source: Historic England

Sources

Books and journals
Bird, R H, Yesterday's Golcondas, (1977), 108
Clough, R T, The Lead Smelting Mills of the Yorkshire Dales, (1980), 233
Raistrick, A, Lead Mining in the Mid Pennines, (1973), 13-49
Dickinson, J M, Gill, M C , 'British Mining No.21' in The Greenhow Mining Field: An Historical Survey, (1983), 65-72

Source: Historic England