The china clay industry of Cornwall had its small beginnings with Cookworthy's extractive discoveries of the perfect components for making industry and also, with its production of hard china which had been a secret of the two million tons of china clay and china stone a Chinese for centuries from the 1750's.
Many people who know the West Country must be aware of the industry from the immense white sand-hills and the deep pits beside them which have turned the hinterland of St. Austell into a lunar like landscape of strange beauty. But it is in its decomposed form that this granite has given rise to arguably the largest single industry that the county has known – the production of china clay. Also known as kaolin, china clay in Cornwall mainly comes from the area north of St. Austell. It comes from feldspar, one of the constituents of granite, and is, technically, a hydrated silicate of alumnia. The decomposition of granite, over millions of years, has been largely caused by hydro-thermal activity resulting from the action of radioactive minerals found in the granite. Deposits occur also in West Cornwall, near St. Just, on Bodmin Moor and at Lee Moor on the south west fringe of Dartmoor.
In the middle of the 18th century much effort was expended in the western world in trying to discover the secret of making hard porcelain which the Chinese had perfected – hence the name kaolin. It was William Cookworthy (1705-1780), a Plymouth apothecary born in Kingsbridge, Devon, who, using china clay and china stone from Cornwall, achieved the manufacture of the elusive product in Plymouth. He found china clay in 1746 at Tregoning Hill, near Helston and later near St. Stephen and St. Austell.
Soon after this potters from Stoke-on-Trent – Wedgewood, Spode, and Minton – mined china clay in Cornwall following legal battles over patents and rights; but the exploitation of this mineral was taken up in the early 1800's by local entrepreneurs such as the Stocker, Lovering and Martin families who responded to the growing demand for china clay by an ever-widening range of industries – paper making in particular.
China clay in the 19th century was extracted from the many pits using mining methods reminiscent of the tin and copper mining industries, engine houses then being a feature of the china clay landscape as much as in the tin and copper areas of the county. In 1800 the production of china clay was a little less than 2,000 tonnes a year but by 1850 this had risen to about 50,000 tonnes and by 1913 to 838,000 tonnes.
The industry was, throughout this 100-year period, very labour intensive, the main tasks in the mining and processing of the clay – removal of overburden, rock and sand, the operation of settling tanks and mica drags and the drying and loading of clay – being done with pick and shovel and other tools and mostly outdoors in a battle with the often hostile Cornish weather. The introduction of plant and machinery to aid production was, in the 19th century, a gradual and steady process. Steam engines for pumping and winding spoil began to be used in the 1830's; coal-fired dryers were first used in 1845 and hoses – later to be known as monitors – for washing the clay from the stopes came into use in 1878. The first steam excavators were in use by the beginning of the First World War and in 1911 the first filter presses, for de-watering the clay slurry, were introduced.
The many village communities such as St. Stephen, St. Dennis, Roche, Bugle, Stenalees, Nanpean, Foxhole and Whitemoor which grew up around the clay works developed their own unique religious and social cultures. Some families could boast of men "in the clay" for four generations.
The industry has always benefited from several natural advantages, such as a ready supply of water used extensively in the mining and refining processes, the proximity of the deposits to local ports, and the ability to use gravity to transport clay in liquid form from the "uplands" to the coast. The clay has been shipped from Fowey, Par, Charlestown and Pentewan – to other parts of the UK (particularly to the Mersey en route to the Potteries) and to more than 50 countries overseas.
Up to the 1930's the mineral deposits were, with very few exceptions, in the ownership of about a dozen landed estates, which levied dues on each tonne of clay produced but which did not themselves, with one or two exceptions, take an interest in production which was carried out by firms which, in 1913, numbered about 100. These firms employed around 5,000 men and also women and boys.
The industry suffered a widespread strike in 1913, involving bitter confrontations between the workmen and the Glamorgan police who were drafted in by the authorities. These events were vividly dramatised in the film Stocker's Copper. This disruption was, however, small compared with the sudden impact of the First World War. Markets in Europe were closed or restricted and shipping was seriously curtailed. In spite of these restrictions the half dozen larger firms were able to adapt and rely on their cash reserves to get them through the war period; but the smaller producers of the lower, and less profitable, grades of clay suffered severely and, they resorted to ruinous price cutting. Towards the end of the war some of the more enlightened employers, realising that prices had to be maintained if the industry was to have a healthy future, formed a trade association – Associated China Clays – in 1917, which most of the producers joined and which fixed production quotas and the prices charged to customers for the whole industry. This achieved a considerable element of stability. The war had also made it clear that competition between scores of producers made no sense and in 1919 three of the largest firms – the West of England Company, Martin Brothers and the North Cornwall China Clay Company – amalgamated to form English China Clays Ltd, the company which dominated the industry until the end of the 20th century.
The recovery in the 1920's was spasmodic and in the 1930's trade was also at a relatively low level. In the 20 years from 1919 to 1939 total production exceeded that of 1913 in only two years – 1925 and 1927. In part these figures reflect the drive by countries overseas – particularly the USA – to develop their own china clay deposits to ensure continuity of supply. The bringing into existence in 1919 of English China Clays Ltd provided the opportunity for many of the smaller firms to sell their operations to the 'combine' which enabled English China Clays to run these works with a level of technical, marketing and administrative support which the smaller firms could not match.
In 1932 the second major amalgamation took place when English China Clays, HD Pochin and Lovering China Clays pooled their assets and resources to form English Clays Lovering Pochin & Co Ltd – known as ECLP – in which each of the companies held shares with English China Clays having the majority. One or two sizeable firms remained independent but, in the coming decades, all of them were eventually taken over by English China Clays.
The 1920's saw the introduction of chemical refining systems – a significant move in fighting American competition – and clay works began to be electrified by the use of gas and oil engines to generate power and also by drawing power from the National Grid. In 1936 ECLP commissioned, at Nanpean, a large coal-fired power station which made the company almost self-sufficient in electricity supply. The first rotary (mechanical) dryer was introduced in 1939 – a major advance on the traditional coal-fired pan kiln. Greater emphasis was placed on responding to the technical requirements of customers and new products, such as calcined clay branded as 'molochite', were developed.
As in 1924 the outbreak of war in 1939 had an immediate impact on the industry. Total output in 1939 was 707,967 tonnes and by 1942 output had dropped to 175,000 tonnes, less than half the output of the middle years of the First World War. Exports slumped more heavily than home trade. Between 1939 and 1945 the Government, through the Board of Trade, exercised a strong influence on the industry by the introduction of a "concentration scheme" designed to focus clay production into the most efficient pits and release men for active service. Only 23 pits remained in operation and around 70 were shut down, some never to re-open. The negotiations by which this scheme was set up were prolonged and contentious, the few pits owned by UK paper makers being the particular objects of dispute, which culminated, in the middle of the war, in an acrimonious court case. A consequence of the concentration scheme was that the industry featured on the radar of the Board of Trade immediately after the war when the board undertook a detailed investigation of the industry and other industries, producing, in 1948, a working party report which deprecated the failure of the industry to introduce up-to-date methods of production.
There was fear in the industry that the Labour Government, having nationalised the coal industry, would do the same with the china clay industry. Sir John Keay – knighted in 1950 – was the managing director of ECLP and he led the industry during the war in its dealings with the Board of Trade and, at the same time, laid plans for its development when trade returned to normal. The investigations by the Board of Trade did not result in nationalisation and had the positive effect of enabling the industry to put pressure on the appropriate government departments to make men and materials available to help the industry recover. Further mechanisation was introduced in the war years, including turbo shelf dryers and continuous refining systems (by ELCP but not by the surviving smaller operators), and fundamental research was aided by the purchase in 1946 of the first electron microscope as part of a programme of greater concentration on technical development.
ECLP spread its activities after the war with the acquisition of Selleck Nicholls & Co Ltd, a local building contractor and quarry owner from which sprang a new business – the 'Cornish unit' system of building which was marketed in many parts of the UK and which was encouraged by the Government in its drive to repair the damage inflicted on the country's infrastructure by bombing during the war. This system was applied to the construction not only of houses but also schools, offices and hospitals. More than 40,000 units were built in the UK. Use was also made of the sand which was a waste product of china clay production and helped boost the fortunes of the company in the difficult trading conditions after the war. The expansion of china clay from the end of the Second World War to the end of the 1980's was rapid. ECLP & Company's output of china clay reached the 1 million tonne mark in 1955 and 2 million tonnes in 1964.
The relative remoteness of the industry from the industrial supply centres in the UK encouraged ECLP to become largely self-sufficient in the provision of skills and services ancillary to the trade. Supporting businesses were established in the removal of overburden and waste materials (Western Excavating Co Ltd), in transport (Heavy Transport Co Ltd which had a fleet of lorries which covered 13 million miles a year), and in engineering (Charlestown Engineering). The engineering and process development functions were particularly important, designing machinery which was used not only in the china clay industry but was also sold all over the world. The local ports of Par and Fowey were acquired and equipped with modern handling gear, the former being recognised as the busiest port, by reference to use of quay space, in the UK – its record was the handling of 22 vessels on a single tide.
The ever-increasing output in these years brought the problem of the disposal of waste material into prominence – for every tonne of clay produced there are nine tonnes of sand and rock – and new mica dams and sand tips were constructed to impound this material, partly in response to new regulations introduced after the Aberfan disaster of 1966. Amid much debate on the scenic merits, or otherwise, of the clay landscape, measures to soften its harsher features were introduced and the concentration of production into fewer pits – only seven now are active – has resulted in new features, such as the now disused and water-filled Blackpool pit, of more than 300 acres.
In the second half of the 20th century the English China Clays Group expanded into quarrying, building and construction, into other minerals (ball clay and celestine), and several other activities, some of which had only a tenuous connection with china clay. The clay business continued to be the core of the enlarged group and overseas deposits were developed in France, the USA, Spain, Portugal and other countries. The paper industry kept its place as the premier customer but its use of other minerals – especially calcium carbonate in the form of chalk and marble – created a rival to china clay for paper filling and coating and the group became a producer of these minerals in the UK and overseas.
By the late 1900's the ECC Group embraced a large worldwide network of production units and sales offices. It is recorded that, in 1969, when the group celebrated its 50th anniversary some 11,000 people were employed worldwide. The shares of the ECC Group were acquired in 1999 by Imerys, a French company which is a world leader in the supply of a variety of minerals to many end users. The clay operations in Cornwall are an important part of the Imerys Group but the china clay output from Cornwall – now less than 1 million tonnes – has been overtaken by output from the US and Brazil. In July 2006 Imerys announced the loss of 800 jobs from the china clay industry around St. Austell. Par docks ceased to operate as a port and is now used just as a drying plant, with the railway line to Fowey docks converted to road used to ship the clay from there.
The uses to which Cornish china clay is put remain as wide as ever – not only in paper and ceramics but also in PVC materials, cables, belting, tyres, films, paints, fertilisers, protective coatings, pharmaceuticals among others.
The industry has an intriguing history and by proving itself able to adapt over more than two and a half centuries to the demands of a changing industrial environment, remains alive and well.
William Cookworthy Wheal Martyn China Clay Heritage Centre The Clay Trails
St. Austell Charlestown Par Pentewan Fowey Roche St. Dennis
Mining in Cornwall