Details

The monument includes the buried remains of three intact stone-built open heap
coke bases which were used to produce coke for a nearby 18th century iron
furnace, together with remains of the furnace slag heap. It is located on
level ground between the River Marron and a steep bank 220m north of Oldfield
Bridge. Little Clifton Furnace was the first coke-fired iron furnace in
Cumbria, commencing operations in 1723 and producing cast iron until its
closure in 1781. Locally mined coal was used to heat the iron ore for smelting
but before it could be used the coal had to be cleaned. This cleaning
operation converted the coal into coke and the process employed here at Little
Clifton was described by Gabriel Jars in 1765, who noted that round areas
about 3.5m in diameter were filled with large pieces of coal to form a cone-
shaped pile some 1.5m high. The coal was arranged in such a manner as to allow
air to circulate through the pile, then lighted coal was placed into the top
of the pile and the whole covered with layers of straw, earth and coal dust.
Two workers were employed to oversee the whole operation and once the coal had
been converted to coke it was taken to the furnace to be used in the iron
smelting process. Remains of these three coke bases were visible until the
1980s when they were covered over by earth during landscaping; they now lie
buried and undisturbed. A short distance to the north is an irregularly-shaped
flat-topped mound of furnace slag up to 2.5m high. This represents the waste
product from the iron smelting process.
A number of features are excluded from the scheduling; these are all
fenceposts, gateposts, a telegraph pole and the timber posts which support the
horse jumps; the ground beneath all these features, however, is included.

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

Source: Historic England

Reasons for Scheduling

Coal has been mined in England since Roman times, and between 8,000 and 10,000
coal industry sites of all dates up to the collieries of post-war
nationalisation are estimated to survive in England. Three hundred and four
coal industry sites, representing approximately 3% of the estimated national
archaeological resource for the industry, have been identified as being of
national importance. This selection, compiled and assessed through a
comprehensive survey of the coal industry, is designed to represent the
industry's chronological depth, technological breadth and regional diversity.
Coking is the process by which coal is heated or part burnt to remove volatile
impurities and leave lumps of carbon known as coke. Originally this was
conducted in open heaps, sometimes arranged on stone bases, but from the mid-
18th century purpose built ovens were employed. By the mid-19th century two
main forms of coking oven had developed, the beehive and long oven, which are
thought to have been operationally similar, differing only in shape. Coke
ovens were typically built as long banks with many tens of ovens arranged in
single or back to back rows, although stand alone ovens and short banks are
also known. They typically survive as stone or brick structures, but earth-
covered examples also exist. Later examples may also include remains of
associated chimneys, condensers and tanks used to collect by-products. Coke
ovens are most frequently found directly associated with coal mining sites,
although they also occur at ironworks or next to transport features such as
canal basins.
Coal occurs in significant deposits throughout large parts of England and this
has given rise to a variety of coalfields extending from the north of England
to the Kent coast. Each region has its own history of exploitation, and
characteristic sites range from the small, compact collieries of north
Somerset to the large, intensive units of the north east. All surviving pre-
1815 ovens are considered to be of national importance and merit protection,
as do all surviving examples of later non-beehive ovens. The survival of
beehive ovens is more common nationally and a selection of the better
preserved examples demonstrating the range of organisational layouts and
regional spread is considered to merit protection.

Little Clifton coke bases are the sole surviving example of 18th century open
heap coke producing bases. They now lie buried and undisturbed and along with
the nearby furnace slag heap will retain important technological information
on 18th century open heap coking and iron smelting.

Source: Historic England

Sources

Books and journals
Jars, G, Voyages Metallurgiques, (1765), 235-7
Marshall, J, Davis-Shiel, M, Industrial Archaeology of the Lake Counties, (1977), 250-1
Other
SMR No. 5653, Cumbria SMR, Little Clifton, (1987)

Source: Historic England