Stone in Wales Conference [2002]

Abstracts of a conference 'Stone in Wales' held at the National Museum & Gallery Cardiff, April, 2002. Papers from this conference will be published by Cadw:Welsh Historic Monuments, in September 2002. For futher details of the newly formed Welsh Stone Forum contact Dr Jana Horak, Department of Geology, National Museums & Galleries of Wales, Cardiff CF10 3NP, jana.horak@museumwales.ac.uk.or Dr Tim Palmer, University College of Wales, Aberystwyth, tjp@aber.ac.uk.

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Contents:

1. Slate walling on the Wales Millennium Centre: an ancient craft in a climate of risk-aversion [KEYNOTE ADDRESS]; Jonathan Adams, (Percy Thomas Partnership)
   
   
2. The language of it builders: stone in the vernacular of Northwest North Wales; Judith Alfrey, (Cadw: Welsh Historic Monuments)
   
   
3. The indigenous buildings materials of Northeast Wales Roger Bennion¹, Philip Ebbrell² & Kirsty Martin³, (Royal International Pavilion. Llangollen¹, Denbighshire CC², Wrexham CC³)
   
   
4. The Carved Stone Decay in Scotland Project: an introduction to the research in progress. Susan Buckhan (Council for Scottish Archaeology)
   
   
5. Stone in building cultures: traditional surface treatments, with particular reference to Wales. Peter Burma, Rory Young
   
   
6. Drystone walling in Wales Philip Clark (Dry Stone Walling Association)
   
   
7. The stones of Valle Crucis Abbey - their life story David Crane (Friends of Valle Crucis Abbey)
   
   
8. The stones of Abbey Cwmhir John Davies (Countryside Council for Wales)
   
   
9. Patterns from the past: field boundaries in the historic landscape John Griffith Roberts (Gwynedd Archaeological Trust)
   
   
10. The building stones of Cardigan and St Dogmaels - a French connection? Dafydd Elis Grufydd (Trinity College, Carmarthen)
    
    
11. The building history and stones of St Davids Cathedral Very Revd, Wyn Evans¹ & Dyfed Elis Grufydd² (St. David's Cathedral¹, Trinity College, Carmarthen²)
    
    
12. Mona Marble: characterisation and usage. Jana Horák (National Museums & Galleries of Wales)
    
    
13. Writ in stone: carving out the myths. Thomas A. Hose (Buckinghamshire Chilterns University College)
    
    
14. The geology of the building stones of Wales [KEYNOTE ADDRESS]; Graham Lott, R. A. Waters, D. Wilson, J. R. Davies and W.J. Barclay (British Geological Survey)
    
    
15. Planning for the supply of building stone in England. Brian Marker (DTLR)
    
    
16. A future for stone: the Scottish Stone Liaison Group [KEYNOTE ADDRESS]; Andrew A McMillan (Scottish Stone Liaison Group)
    
    
17. From mud to roofing slate: How Wales' best known building stone was formed [KEYNOTE ADDRESS]; Richard Merriman (British Geological Survey)
    
    
18. For stone read Clom - what happened if there was no stone available. Gerallt Nash (National Museums & Galleries of Wales)
    
    
19. Why is Portland Stone special? Tim Palmer (University College of Wales, Aberystwyth)
    
    
20. Slate as a sustainable building material Christopher Powell (Cardiff University)
    
    
21. The White Roofs of the St Davids Peninsula Philip Roach (Pembrokeshire Coast National Park Authority)
    
    
22. Sources of imported building stone Eric Robinson
    
    
23. Build and re-build - the message of stone in the churches of east Wales Bob Silvester (Clwyd & Powys Archaeological Trust)
    
    
24. Stone versus timber: preferences and prejudices in Medieval and early-modern Wales Richard Suggett (Royal Commission for Ancient & Historic Monuments in Wales)
    
    
25. The Welsh stone industry - its development and trade Ian Thomas (National Stone Centre)

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KEYNOTE ADDRESS

Slate walling on the Wales Millennium Centre: an ancient craft in a climate of risk-aversion

Jonathan Adams, (Percy Thomas Partnership)

The concept for the design of the external walls of the Wales Millennium Centre was founded on logic and opportunism, - there is an abundance of slate waste available mainly in North Wales, and this would present a means of making a durable, high quality stone envelope befitting a major new civic building at a low cost. At the same time, the project would be using a material and a form of skilled labour synonymous with Wales.
The process of turning a simple, economical idea into reality has been fraught with complications. Modern construction contracts often transfer nearly all of the risk onto the builder. As a result of this the large contractors are reluctant to make use of materials which are not factory produced, or to be in the position where they depend on specialised skills, because they see both as being highly risky. This tendency, which has only been reinforced by the Egan Report, is undermining efforts to widen the use of indigenous building techniques.
It has taken years for Percy Thomas Architects to 'win' the argument for using waste slate as a contemporary architectural material. The talk explains how it was done.

The language of it builders: stone in the vernacular of Northwest North Wales

Judith Alfrey, (Cadw: Welsh Historic Monuments)

The use of locally available materials is a defining characteristic of vernacular building. Traditional buildings in North Wales apparently trace geography of stone. But even in a landscape of stones, there was differential access to the materials and skills needed in building. Stone was superficially abundant, but it was rarely free, and its use in building provides a valuable index of access to resources. Its introduction for even the humblest dwelling in the 19^th century, and its common use thereafter in buildings of all ranks established a common language of building. But in the vocabulary of its detail - in the selection of material, and the techniques of working and construction - there is a clear social geography. In the detail of their construction, vernacular buildings do not simply express the distribution of building materials in North Wales, but can also illuminate an intricate social and economic history.

The indigenous buildings materials of Northeast Wales

Roger Bennion¹, Philip Ebbrell² & Kirsty Martin³, (Royal International Pavilion. Llangollen¹, Denbighshire CC², Wrexham CC³)

This is a study, which attempts to categorise the indigenous building materials of Northeast Wales and identify original and new sources in order to help reverse the dilution of local distinctiveness by the inappropriate use of imported materials.

The Carved Stone Decay in Scotland Project: an introduction to the research in progress.

Susan Buckhan (Council for Scottish Archaeology)

Anecdotal evidence shows that gravestones are deteriorating at an alarming rate. At present the exact scale of this problem - and the factors responsible - are not yet fully appreciated. This paper will outline the initiatives currently being taken to record and manage carved stone decay in Scottish graveyards. The Carved Stone project is a joint initiative between the Council for Scottish Archaeology and Historic Scotland, with the National Committee on Carved Stones in Scotland and the Royal Commission on Ancient and Historic Monuments in Scotland acting in a advisory capacity. The project involves a wide range of participants, from field surveyors based in the local community and those with a duty of care for gravestones - most notably LA cemetery managers - to archaeologists and conservation specialists responsible for drawing up policies for the long-term protection of this important cultural resource. This paper will discuss the methodology devised to record environmental mechanisms of decay in conjunction with factors of human intervention and outline the research agenda of the project.

Stone in building cultures: traditional surface treatments, with particular reference to Wales

Peter Burma, Rory Young

This talk will look at and illustrate surviving evidence for surface treatments on early and late medieval high status buildings, post-medieval buildings of the 16^th-early 18^th centuries, then at what happened after the introduction of cement, and the present struggle to get back to a lime-based culture for older buildings, whether vernacular or high status. Understanding the way in which surfaces have been treated on stone structures is crucial to an accurate understanding of their cultural value, and equally crucial to understanding how best to repair and conserve them for the future.

Drystone walling in Wales

Philip Clark (Dry Stone Walling Association)

Like other upland areas of Britain, Wales has had dry stone work for many centuries, for boundaries, buildings, and retaining walls. Style is dependent on local stone; earth-filled, stone-faced banks (cloddiau) were once widespread. Enclosures and, later, the management of large estates added more field and boundary walls; in the 20^th century changing agricultural practices and social conditions reduced the number of viable structures. Certain areas kept up more walls than others did: e.g. much of North Wales, the "mountain" farms above the South Wales valleys. Recent revival of the craft has been aided by the grant regimes and by various organisations: the National Trust, CCW, the National Parks, the Dry Stone Walling Association, &c - and by the fashion for "instant heritage" structures commissioned by local authorities in towns and alongside roads. Field walls are still a crisis area, but the pioneer "Walls of Llangynidr" scheme in Breconshire points a community-based way forward.

The stones of Valle Crucis Abbey - their life story

David Crane (Friends of Valle Crucis Abbey)

Valle Crucis Abbey was founded in 1200, just a few miles outside Llangollen, by Madog ap Gruffud, ruler of northern Powys. He gave the land 'a small meadowy flat, watered by a pretty stream and shaded with hanging woods' (Pennant 1784) to the Cistercian monks of Strata Marcella for the establishment of a daughter abbey. Probably living in timber accommodation, they immediately began the construction of the permanent stone buildings, the ruins of which we see today.
Here we will trace the life story of the stones of Valle Crucis. We will examine the different types of stone used for the building and ornamental work, and the sources of that stone. We will look at the way the stone was worked and the marks of the masons that did the work. We will investigate what the stone can tell us about the history of the Abbey and the change in the use of stone over the centuries for various rebuilding work. Finally we will examine what happened to the stone of Valle Crucis Abbey following the dissolution in 1536, to see what other uses it was put to, and look at some of the more recent restoration work to the Abbey.

The stones of Abbey Cwmhir

John Davies (Countryside Council for Wales)

The ruins of the abbey (SO 055711) lie in the field opposite the Victorian mansion in the village of Abbey Cwmhir, Radnorshire, Powys. The remaining walls show the outline of the huge (74.46 m) nave of the church. Raleigh Radford (1982) stated that freestone used in the building was Grinshill Stone from NE of Shrewsbury, and the Gothic carving was of the 2^nd and 3^rd decade of the 13^th century. In Radford's opinion, this was the work of Llewelyn 'The Great' (d. 1240), between 1228 and 1231. Because Grinshil Stone is a honey-coloured arkosic sandstone, it is distinctive in Radnorshire, where the local stone is a dark green-grey sub-quartzite, or grey slate. It is thus easy to map the distribution of recycled stone in the surrounding countryside, after work ceased (c. 1234), but certainly after the Dissolution of the Monasteries (1539-42).
This is an account of the work of the Abbey Cwmhir Trust since 1987 to identify and record the re-use of stone, which has provided a valuable archaeological tool to aid the interpretation of the history of this part of Wales. The results of the work have implications for other monastic churches and castles in Wales, such as Whitland, St Dogmaels, Strata Marcella, Strata Florida, Catell-y-bere, Carmarthen etc., since all of these used imported and distinctive freestone. The work throws light on the 'Greatness' of Llewelyn 'The Great' as a promoter of fine buildings, and gives the lie to the suggestions that we as a Nation have never appreciated fine architecture.

Patterns from the past: field boundaries in the historic landscape

John Griffith Roberts (Gwynedd Archaeological Trust)

Field boundaries of various kinds represent one of the most striking, ubiquitous and defining characteristics of the Welsh landscape. Many of the country's field boundaries are either early in date or follow patterns of demonstrable antiquity, whilst the eighteenth and nineteenth century enclosure has produced the distinctive geometrical and topography-defying boundaries of the uplands. Recent hedgerow legislation, biodiversity related grants and the Tir Gofal agri-environment scheme mean that considerable funds are being directed towards the maintenance and restoration of field boundaries. However, they are relatively understudied, and there is little cohesive awareness of why boundaries are of value, or of exactly what it is that we hope to preserve by investing in their maintenance. In some cases, the very funds that are provided for their maintenance may be eroding their most important aspects. Namely that they make a fundamental contribution to the character and distinctiveness of Welsh landscapes at a local level.
It is also important to see field boundaries as more than the sum of their parts; boundary networks map out changing patterns of land use and society through history. This talk will investigate these issues with reference to the initial findings of a project being jointly funded by the Countryside Council for Wales and Cadw: Welsh Historic Monuments looking into the variety and character and history of field boundaries across Wales.

The building stones of Cardigan and St Dogmaels - a French connection?

Dafydd Elis Grufydd (Trinity College, Carmarthen)

With the exception of Portland Stone, Bath Stone and Larvikite, building stones derived from sources beyond Offa's Dyke are conspicuously absent in Cardigan. Here, and in the neighbouring village of St Dogmaels, extensive use has been made of slate and sandstone derived from local quarries. What is particularly intriguing is the way in which these materials have been utilised by local masons in buildings pre-dating the early twentieth century. Courses of dressed slate slabs often alternate with either single or double courses of dressed sandstone blocks. Such banding is prominent in St Dogmaels, not only in houses and cottages but also in the abbey walls, the only Tironian abbey established in Wales and England. Robert fitz Martin, the Anglo-Norman lord of Cemais and the abbey's founder, brought a band of monks from the mother abbey of Tiron (Thiron) in the diocese of Chartres. He may also have introduced a building tradition (and possibly some building stones), which are peculiar to that part of Cemais between Cardigan and his castle at Newport.

The building history and stones of St Davids Cathedral

Very Revd, Wyn Evans¹ & Dyfed Elis Grufydd² (St. David's Cathedral¹, Trinity College, Carmarthen²)

This paper represents the culmination of a project long discussed by the authors of identifying the stone used in the construction of St Davids Cathedral within the various phases of its development, following detailed examination of the existing structure.

Mona Marble: characterisation and usage.

Jana Horák (National Museums & Galleries of Wales)

Mona Marble is a green serpentinite, variably brecciated with either a white calcite matrix or cross cut by calcite veins. It occurs as isolated outcrops within the Precambrian/Early Cambrian metasediments on Holy Island and the adjacent mainland of Anglesey. In common with many other building and ornamental stones, considerable confusion as to the nature of this rock has arisen in the literature and little is known about its extraction.
The first documented reference to exploitation of the stone is made by Angharad Llwyd in her prize essay (1833), when she refers to the Verde Antique of Rhoscolyn. Watts (1916) in his classic work on Building Stones also cites the use of Mona Marble in the construction of Bristol, Peterborough, Truro and Worcester Cathedrals during the period 1886-1895, but provides no details as to the specific location of extraction.
The most extensive promotion of Mona More was undertaken by George Bullock. During the early part of the 19^th century he advertised the merits of the stone going as far as naming it verde de Mona. However, the exact source of these pieces, often fireplaces, has not been verified, for although Bullock owned small quarries near Llanfechell in northern Anglesey, there is no record of him having worked quarries on Holy Island. It is pertinent to note that he carried out much of his work during the Napoleonic Wars, when trade embargoes would have impeded the legal import of ornamental stone from the continent. In 1815 Bullock was commissioned by the Prince Regent to supply furniture to accompany Napoleon Bonapart to St Helena. Included within this was a table inlaid with Mona Marble, this item resides on St Helena to this day.

Writ in stone: carving out the myths

Thomas A. Hose (Buckinghamshire Chilterns University College)

Observations on Welsh geology, aided by the quality and sheer quantity of the country's natural and artificial rock exposures, have informed geology's development since at least the late sixteenth century. The often deliberate obliteration of the relics of the extractive industry heritage is in marked contrast to the preservation, renewal and promotion of the architectural and industrial heritage founded upon the wealth it created. This extractive industry landscapes' sanitization must be urgently addressed before its many unique windows into the remote past are lost. The promotion of a successful conservation and limited exploitation strategy - "geotourism" - for geosites is reliant upon gaining and holding the support of politicians, planners and developers by demonstrating their benefits and potential to the tourism and outdoor recreation industries. Academic geologists and conservationists must recognise the need to address the significance of their work to other than committed audiences and constituencies. The successful promotion of geoconservation in Wales depends upon adopting appropriate communication policies, interpretative strategies and guidelines to meet the needs of non-committed audiences and constituencies grounded within the developing framework of "geotourism". This presentation focuses upon the concept through a theoretical discussion grounded in case study analyses focused on the Welsh Borderland.

KEYNOTE ADDRESS

The geology of the building stones of Wales

Graham Lott, R. A. Waters, D. Wilson, J. R. Davies and W.J. Barclay (British Geological Survey)

Wales is a stone country. Its varied sequence of rocks has been continuously exploited to provide a wide range of stone for building purposes. The surviving vernacular, historic and industrial buildings in villages, towns and cities across the Principality provide evidence of an extensive stone quarrying industry that is now, with few exceptions, largely forgotten. Transportation problems resulting from the mountainous nature of much of the country has meant that with one prominent exception, the roofing slate industry in North Wales, stone quarrying in general supplied local, rather than wider UK or international needs and markets.
Most of the rock successions that crop out within the Principality have yielded stone for local building purposes. Each quarried stone has generally developed a local sphere of influence. The highly variable lithologies of the Precambrian to Lower Palaeozoic successions, of rural mid and north Wales, have provided stone for most of the main settlements in the area. Most such stones are hard, dark coloured, intractable, metasedimentary rocks that were not easily dressed and consequently appear in buildings as irregular blocks of very variable size. By Contrast, the overlying green and reddened sandstones of the Devonian provided more easily dressed stone and consequently facilitated a change in building style across their outcrop.
The Upper Palaeozoic rocks of the Carboniferous have provided the grey limestones and sandstones, familiar throughout the industrial settlements of the Coalfield areas. Hence the sandstones provide not only the ubiquitous blue-grey, dressed ashlar blocks, but also the larger sawn stones needed for bridges and other industrial structures. Some of the sandstone beds even provided adequate stone roofing 'slate'.
Though very restricted in their outcrop, the youngest rocks of Wales, from the Triassic and Lower Jurassic systems of the Mesozoic, have provided colourful conglomerates, sandstones and limestones. Though these stones are locally common in vernacular housing and were also popular with those late Victorian architects, who championed the polychromatic styles advocated by John Ruskin and others, they also appear in a similar decorative fashion in many medieval buildings.
Although at first glance an unlikely source of building stone, even the well-rounded cobbles and boulders from the river gravels and glacial deposits of the Quaternary succession have in areas lacking suitable alternatives, commonly been used for building purposes. Whilst the indigenous stones of Wales have served most of the building needs of the local population, the lack of good freestones, like the Jurassic limestones of Bath and Portland, has meant from earliest times such stones were often imported for use in prestigious building projects.

Planning for the supply of building stone in England

Brian Marker (DTLR)

The building and roofing stone industry is locally important in many parts of the England, and some sources, such as Portland, are nationally and water and other chemical elements in their crystal structure. Such properties enable clays to respond relatively rapidly to changes in temperature and pressure in the upper part of the Earth's crust. These changes began when mud in the Welsh sedimentary basin was buried beneath several kilometres of younger sediment. The clay minerals responded to burial by expelling water and growing larger crystals, transforming soft mud into hard mudstone. The final transformation of mudstone to slate took place when the Welsh basin was compressed and sedimentary rocks were folded to form part of a mountain chain some 400 million years ago. During folding the clay minerals in mudstone recrystallised to thicker, but less hydrous, scaly crystals arranged along micron-spaced planes that formed a slaty cleavage.
The quality of roofing slate is largely governed by the effectiveness of the final recrystallisation. In the best Welsh slates clay mineral crystals are 2-3 times thicker than those in typical mudstones, and this produces the most durable and impervious roofing material. When the cleavage fabric is closely spaced and parallel, the slate can be split to produce a roofing tile with a finished thickness of only 4mm. Other minerals, particularly quartz and feldspar, act as fillers and give the slate a bulk strength. Too much of these minerals increases the thickness and coarsens the surface finish of the slate; too little produces a soft slate with low strength. Colour is not a guide to quality and generally results from the presence of small amounts of iron-rich minerals. Red and purple slates contain disseminated hematite (Fe₂O₃), whereas grey and blue slates contain variable amounts of pyrite (FeS₂). Oxidation and hydration of pyrite causes the red-brown staining characteristic of rustic slates, whereas the formation of sulphate minerals from pyrite is the main cause of slate deterioration.

KEYNOTE ADDRESS

A future for stone: the Scottish Stone Liaison Group

Andrew A McMillan (Scottish Stone Liaison Group)

The Scottish Stone Liaison Group (SSLG) was officially launched by the Scottish Executive in May 2000. The SSLG owes its origins to the far sighted initiative of Historic Scotland who brought together in 1995 representatives of a wide range of bodies interested in Scotland's stone built heritage. It seeks to promote all aspects of stone including conservation, repair and maintenance, use of stone in new build, together with the materials.

KEYNOTE ADDRESS

From mud to roofing slate: How Wales' best known building stone was formed

Richard Merriman (British Geological Survey)

Wales is famous for producing some of the best roofing slates in the world. But the most durable of all roofing stone was created from soft mud deposited in the oceanic sedimentary basin that covered Wales more than 450 million years ago. This remarkable transformation of natural materials was largely controlled by the crystal-chemical properties of the clay minerals that are found in both mud and slate. Clay minerals are characterised by very small crystals with the ability to attract or release increasing since the start of the Industrial Revolution. How are these folk going to be interested in geology, which traditionally has been seen as expressed in landscapes, coastal cliff section, mines and quarries?
The use of bilingual urban geology town trails is explored as a medium for introducing the public to geology. Through its use in the urban environment, it is in the hoped that in the future people might understand why it is important to preserve our geological heritage. The series produced by NEWRIGS (North East Wales Regionally Important Geological/geomorphological Site) group entitled "Walking through the Past" will be highlighted.

For stone read Clom - what happened if there was no stone available

Gerallt Nash (National Museums & Galleries of Wales)

What were the options available to traditional builders when stone was in short supply or could not be afforded? In east Wales, timber offered an alternative constructional material for erecting walls, but elsewhere, and more especially in the west, this was also at a premium. The answer for many was clom - a mixture of clay and small aggregate. This talk will examine the ways in which this widely-used material replaced stone as the main building material especially in the houses of the rural poor.

Why is Portland Stone special?

Tim Palmer (University College of Wales, Aberystwyth)

Although Portland Limestone is primarily thought of as the principal building stone of London, it has also been widely used for administrative buildings in other cities and towns in the UK, including Cardiff. Portland differs from the other Jurassic oolitic limestones from England in three ways: it is nearer to white than honey-coloured; it weathers by slow loss of individual ooliths from exposed faces (rather than alone sedimentary lamination), thus continuously exposing the fresh pale stone beneath; and its strength lies (in marked contrast to Bath Stone) in the individual ooliths rather than the natural calcite cement that surrounds them. These properties can be related to the environmental conditions of the deposition on the shallow sea floor and to the subsequent early geological history of the late Jurassic sediments, on the Isle of Portland. The individual ooliths were strengthened by bacterial attack and the subsequent calcite precipition within them. The early hardening of the stone took place above seal-level, so iron sulphides might subsequently degrade into brown or buff coloured oxides and hydroxides were not deposited, and the whole geological formation was underlain and overlain by clays that prevented the pore spaces between the grains becoming infilled with more than a small volume of natural cement, thus preserving high porosity and permeability.

Slate as a sustainable building material

Christopher Powell (Cardiff University)

The idea and aim of sustainability has arisen fast in recent years both at international and government levels and among individual designers and specifiers. Many of the properties of slate suggest that the material has valuable potential in terms of sustainability. Criteria for judging sustainability of building components over their life cycles are proposed and are related to the performance attributes of slate. The thermal performance of slate is singled out as being particularly favourable. The effect of this is that slate is capable of passive thermal damping of internal components: reducing uncomfortable temperature peaks and troughs over the 24 hour cycle without recourse to engineering remedies.

The White Roofs of the St Davids Peninsula

Philip Roach (Pembrokeshire Coast National Park Authority)

This paper looks at a distinctive building feature, which developed in an attempt to reduce problems experienced with local slate, in both a historical and geographical context. Consideration is given to the evaluation and conservation of the feature, which may be of wider application.
methodology devised to record environmental mechanisms of decay in conjunction with factors of human intervention and outline the research agenda of the project.

Sources of imported building stone

Eric Robinson

While Wales is rich in stone for substantial walling, and what must be the World's best roofing material, for fine mouldings and stone to carry decorative carving, there has always been a need for stone from sources beyond the Severn. An assessment of 'exotic' stone allows us to appreciate the resources committed by communities through History to the buildings we recognise as representing time from the Roman through to Medieval to Victorian years.

Build and re-build - the message of stone in the churches of east Wales

Bob Silvester (Clwyd & Powys Archaeological Trust)

The oldest building in a settlement is often the church. Some have clearly been constructed at a single time, but many others have undergone successive enlargements, additions or modification over the centuries. While the architectural details provide some clues to these changes, the fabric of the church itself can be equally informative. Using data collected during the recent Cadw-funded study of all the historic churches in Wales, this talk will examine three or four churches - Presteigne (Radnorshire), Llanfechain (Montgomeryshire) and Llaynys (Denbighshire) - to demonstrate how the building material can signal complex historical development of each building.

Stone versus timber: preferences and prejudices in Medieval and early-modern Wales

Richard Suggett (Royal Commission for Ancient & Historic Monuments in Wales)

The selection of building materials is by no means always a straightforward matter. Historically, the construction of castles, churches, and houses has involved some interesting and sometimes puzzling choices of building internationally significant. However many sectors are exposed to stong competition from abroad. The volume of production is variable, from small single quarries producing low volumes, to larger companies operating several quarries regularly or intermittently with mobile teams of workers, and even underground mines.
There are increasing restrictions on the working of these materials, for instance in relation to locally, nationally, and internationally important landscape and conservation designations, as well as other land use constraints. Constraints on supply need to be set against the very precise requirements that arise from, for example, factors such as the preferences of architects or for maintaining local vernacular architectural styles and for repair and maintenance of historic buildings and ancient monuments.
Existing Minerals Planning Guidance Note 1 (MPG1) "General considerations and the development plan system" makes brief reference to this industry. In addition, there is a tendency for policies developed mainly with large scale aggregates extraction in mind to be applied to these minerals. There is a need to examine the extent to which that is appropriate and whether a more distinctive policy framework should be developed taking into account policies in, for example, planning policy guidance on planning and the historic environment (PPG15).
Therefore the DTLR has commissioned research to examine planning policy issues fror supply of building stone in England. Work will commence in April 2002 and will alst for about 18 months. The results will inform revised guidance. Since the planning system in England as a whole is currently under reviewe, including the future nature and content of minerals planning guidance the results will have to be adapted to whatever new approach emerges following the debate on the green paper "Planning: delivering a fundamental change" that was published in December 2001.

The Welsh stone industry - its development and trade

Ian Thomas (National Stone Centre)

The development of the production and use of building stone in Wales will be described in a broad historical and geographical context. Building stone cannot be considered in isolation; the industry was predated by the trade in stone implements and superseded at least in scale, by the processing of stone for industry and aggregates.
The paper will also examine the influences upon trade, both within Wales and with the surrounding countries and in particular, conditioning by transport and fashion. Finally, brief consideration will be given to the extent to which awareness of this important heritage is being promoted.