Reasons for Designation
For several millennia the western part of the South West Peninsula, namely
Cornwall and West Devon, has been one of the major areas of non-ferrous
metal mining in England. It is defined here as prospecting, extraction,
ore processing and primary smelting/refining, and its more important and
prolific products include copper, tin and arsenic, along with a range of
other materials which occur in the same ore bodies. Throughout much of the
medieval period most of the tin was extracted from streamworks, whilst the
other minerals were derived from relatively shallow openworks or shafts.
Geographically, Dartmoor was at the peak of its importance in this early
period.
During the post-medieval period, with the depletion of surface deposits,
streamworking gradually gave way to shaft mining as the companion to
openworking methods. Whilst mining technology itself altered little, there
were major advances in ore processing and smelting technologies. The 18th
century saw technological advances turning to the mining operations
themselves. During this period, Cornish-mined copper dominated the market,
although it was by then sent out of the region for smelting. The
development of steam power for pumping, winding and ore processing in the
earlier 19th century saw a rapid increase in scale and depth of mine
shafts. As the shallower copper-bearing ores became exhausted, so the mid
to late 19th century saw the flourish of tin mining operations, resulting
in the characteristic West Cornish mining complex of engine houses and
associated structures which is so clearly identifiable around the world.
Correspondingly, ore processing increased in scale, resulting in extensive
dressing floors and mills by late in the 19th century. Technological
innovation is especially characteristic of both mining and processing
towards the end of the century. In West Cornwall, these innovations relate
chiefly to tin production, in East Cornwall and West Devon to copper.
Arsenic extraction also evolved rapidly during the 19th century, adding a
further range of distinctive processing and refining components at some
mines; the South West became the world's main producer in the late 19th
century.
From the 1860s, the South West mining industries began to decline due to
competition with cheaper sources of copper and tin ore from overseas,
leading to a major economic collapse and widespread mine closures in the
1880s, although limited ore-extraction and spoil reprocessing continued
into the 20th century.
A sample of the better preserved sites, illustrating the technological and
chronological range, as well as regional variations, of non-ferrous metal
mining and processing sites, together with rare individual component
features, are considered to merit protection.
Despite limited damage on the cessation of mining activity, and some
subsequent modification, the remains at Geevor Mine are very well preserved.
The extent and range are outstanding, the near-complete dressing mill in
particular. The 20th century layout is an exceptionally good example of its
kind, demonstrating the systems, technology, and organisation of mines at
that time. There is scope for detailed study and archive research of
features, such as mill equipment; some typical, some unique to Geevor.
Earlier mining processes and practices are represented, and there is
potential for the survival of further underground and buried surface works.
Taken as a whole, the remains illustrate well how mines can impact on the
physical and human landscape, changing surface landforms and settlement
patterns in addition to the underground world. They also show how mining
responded to continuing factors like the need for water used in its
processes, and to changing ones such as widening economies.
Details
The scheduling includes remains of Geevor tin mine, situated on the north
coast of Cornwall, north east of St Just in Penwith. The site occupies a
small valley running north west to the sea, incorporating slight to moderate
slopes, and steep cliffs below. Included in the scheduling is an adjoining
tin works, Rescorla's, and the remains of a Mesolithic flint working floor.
The mine is one of several in the area and is associated with nearby mining
settlements. The scheduling is divided into two separate areas of protection.
Recent surveys provide a detailed history of Geevor. The mine worked tin
lodes trending north west-south east across the coast. In the 20th century,
arsenic and then sulphides became significant by-products. Geevor is one of
only four mines in Cornwall worked to the late 20th century. By this time it
incorporated around ten earlier mines, and was around 800m deep.
Mining started here in the later prehistoric or medieval periods in the form
of tunnels into lode exposures in the cliffs, and outcrops inland. Also, the
valley bottom is thought to have been worked from medieval times for tin,
which would have been exploited by streaming, using water to remove
overburden and waste.
By the 18th century deeper mines were established; one, Wheal an Giver, was
recorded in 1716. People, horse, or water power was used to hoist ore from
shafts, and in dressing and processing it. Steam power was being employed by
1815. Through the 19th century these ventures were consolidated into larger
ones. Under the North Levant group (1851-1891) the dressing floors spread
over the valley bottom, and the mine service area emerged above them.
Production shafts south of the scheduling were linked to the dressing floors
by tramway.
In the early 20th century the mine was developed beneath the sea. North
Levant and Geevor (1906-1911) built the core of the modern dressing mill, and
began Wethered Shaft south east of the scheduling. Both electricity and gas
were introduced and growth continued under Geevor Tin Mines Ltd (1911-1992),
though checked by periodic slumps and the two World Wars. Wethered Shaft was
linked to the mill by aerial ropeway, but was superseded as the main
production shaft by Victory Shaft, south east of centre in the scheduling,
sunk from 1919. The neighbouring Levant Mine was acquired in 1934 and access
to its submarine levels was secured by the mid-1960s. There was also early
investment in compressed air as a power source. The mill was extended and
remodelled in 1912, the first of two Brunton calciners for recovering arsenic
being added in 1913, and a separate area for processing its slimes or waste
by 1925. Its capacity and efficiency were improved by expansion and
re-equipment using chemical, relative density, and magnetic separation
methods. Spoil from nearby mines was dressed for residual minerals, to
maintain throughput.
Mine tours were begun in the 1970s, and growth and modernisation continued
until the world tin price crash of 1985. The miners were laid off by 1990,
and pumping ceased in 1991. Some machinery and fittings were removed for
scrap, or displaced. In 1992 Cornwall County Council purchased the mine as a
heritage centre and initiated a programme of safety and other amenity works,
including shaft capping, securing or reopening adits, and limited
reconstruction.
The remains of the mine are of great complexity, both above and below ground.
This is the result of its long life and relatively recent closure, large
size, intensive working, and frequent reuse or adaptation of pre-existing
structures, earthworks, and tunnels. The remains are complemented by a mine
archive, old maps, and photographs, and are further enhanced by recent
surveys, and by the testimony of former miners.
The following account is intended to outline the remains in the scheduling,
dealing first with those integrated in Geevor Mine at its peak, and then with
abandoned earlier mining features. It is concerned primarily with remains at
or near the surface, owing to lack of access to lower levels at the time of
writing. However, the very extensive deep workings survive, with complex
tunnels and features such as transport and pumping sytems, though flooded to
third level (sea level). The adit draining to this level is visible at the
base of the cliffs.
The surface layout of the site, as developed through the 20th century, may be
divided by function into three main zones. These are focused on Victory
Shaft; their positions and those of their many components reflecting the use
of gravity, and the flow of liquids, in achieving efficient preparation of
the ore. Across the zones, most structures are of concrete, timber, or steel,
with corrugated sheet roofing, and the most recent are of standardised
design. Older granite walling and buildings with slate roofs are
incorporated, however. Notable among these are the stable, carpenter's shop,
and (excluded from the scheduling) the count house in the first zone; the
calciners and slimes plant in the second; and sunken tanks in the third. Much
of the fabric shows joints, blockings, and other evidence of the mine's
evolution.
The zone nearest the valley head contains structures for servicing the mine
with supplies of power, water, tools, and materials, with an office, and
miners' dry or changing house. These are spread along the road towards
Wethered Shaft, and clustered around Victory Shaft, at the top of the next
zone. Most buildings contain machinery and other fittings, and the dry has
graffiti dating from the closure of the mine. The roads and yards between
them have pipe and cable trenches and tram lines in situ. Victory Shaft
retains both its timber framing (with service cables and pipes down to third
level), and its steel headframe above. This has unusual gear for raising
skips and man cages alternately. It also retains the overhead cable from the
winding engine house. The electric winder is in situ, as is the plant in the
compressor house.
The second zone, below this, is dedicated to processing tin and by-products.
The principal structures are the capacious, extended, and adapted mill, and
the slimes plant. These are near complete, with shaking tables for sorting
fine tin from liquified ore and other processing equipment inside; and tanks
and storage bins without. Many machines are from the Cornish manufacturers,
Holmans. Raw materials and waste are represented by a stockpile of Geevor ore
west of the mill (part re-sited); a pile of spoil brought in for reprocessing
to the east; and by parts of the dumps of gravel for sale on either side.
Remains of the routes for liquids and solids through the dressing circuit,
linking buildings and plant, tanks, bins, stockpiles, and dumps, are visible.
These take the form of pipes and channels at ground level and launders,
chutes, conveyors, pipes, and cables above.
Downslope again is the third zone, where further tin was recovered from the
tailings or waste slimes of the second. The tailings stream is fed down the
north east side of the valley. Along its upper course are Geevor's settling
tanks and ponds and sampling huts, connected to each other and the bottom of
the mill by pipes, channels, and launders. Below is another 20th century
tailings works, Rescorla's. This occupies the site of a Levant Mine dressing
complex, and retains its terraces above the cliff and concrete settling
tanks, as well as an earlier header pond. The older mining remains in the
scheduling, not integrated in the system summarised above, mostly relate to
the ventures of the 18th and 19th centuries, although some may be medieval or
earlier in origin. Notable among the visible surface elements are the walls
of a 19th century powder house, or explosives store, sited safely south of
the core of the mine; walling east of the mill, probably part of an arsenic
burning house of similar date; an early 19th century or older water powered
stamps house on the cliff edge; and the chimney of a steam pump house for the
Levant dressing floors. More will survive beneath the debris in the valley
bottom.
Abandoned pre-20th century underground remains also survive within the
scheduling. The recent surveys record shallow workings, both wholly
subterranean and open topped, post-medieval or earlier in origin. They are
diverse in form and function, and have rare features including dome-sectioned
excavated miners' shelters, some with hearths and benches, unknown outside
Geevor. Modified examples of the latter are visible from the surface. These
workings were mostly found filled or choked in the less intensively reworked
ground west and south east of the mill; again, others are expected to remain
buried downlope. In addition, it is considered that the valley bottom
contains remains of medieval or later tin streaming. The massive stone
walling above the cliffs may be retaining streamworking waste.
Finally, flints and a cobbled flint-working surface of the Mesolithic period
(around 7,500 BC) have been found in the valley above Rescorla's.
A number of items are excluded from the scheduling. These are: the
transformer house and adjoining store, the office with count house, the
garage, and the fitting shops, and with all post-mine closure road surfaces,
footbridges, fences, gates and stiles, safety equipment, benches, bins,
services, signs, information boards and exhibits. The ground beneath all
these features is, however, included.
MAP EXTRACT
The site of the monument is shown on the attached map extract.
