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SOME UNUSUAL LOCAL BUILDING STONES ROGER DIXON Introduction Churches provide some of the earliest evidence of building materials that we can actually see around us. Many in coastal Suffolk, although having AngloSaxon origins, were part of the post-Conquest programme of replacing timber structures with stone. Subsequent alterations, enlargements or restoration work serve to illustrate not only changing fashions and styles of architecture and materials, but also changes in industry, agriculture and commerce, and social and political history. They can therefore be invaluable multi-disciplinary educational tools. This paper deals with just some of the aspects of church fabric that are either unusual to Suffolk, or unusual in Britain. By comparison, bricks did not become much used until the reigns of Henry VIII and Elizabeth I, when they became most fashionable – for example in Seckford Hall, built in the 1540s, and the Tudor towers of Waldringfield and Hemley churches. Later, as their use became more widespread, many local clay and brick pits were developed, such as that still surviving at Chillesford today. Flints are another very obvious material and are widely used; they were readily available from beaches and used as cobbles, or roughly dressed by splitting, or finely worked by knapping, as seen in the beautiful flushwork at Ufford church. Exotics Bits of igneous and metamorphic rocks, sandstone and limestone are quite commonly found dotted about in the fabrics of east Suffolk churches. All Saints, Hemley is a good example. Some are evidently much re-cycled and their origins impossible to trace – but they are obviously not ‘local’. Caen limestone was imported by the Normans on a large scale and can be seen as structural elements, quoins and door and window surrounds in a great number of churches. Some stones, Purbeck and Barnack limestone for example, can be identified and are not uncommon in repair work. Possibly the best example of an exotics location is St James church, Dunwich, built on the site of the former leper hospital in 1830 and converted in 1839 to its present gothic style with the exterior clad in stone. The chancel was added in 1881. Over 20 different types of stone can be found in the chancel alone. They are mostly white Caen limestone around windows and doors, and local flint. About 35% of the roughly dressed building stones used are exotic and include red, pink and white granite, black dolerite, basalt and gabbro, white and pink quartzites, gneiss, slate, gritstone, several types of sandstone and limestone, chalk and others. The same rock types can be seen in the nave walls, but local septaria from the London Clay of south Suffolk are much in evidence (over 10% of the materials used) with round flint pebbles from the beach. Most of this stone was recycled from the former leper hospital and previous Dunwich buildings lost to the sea. The nearby ruin on the Greyfriars site and much of the perimeter wall, completed in 1307, contain the same materials. Most of these exotics were imported as ballast used by shipping. After unloading, merchants sold it on as building stone, and it may have been
16 recycled many times. Both the Saxons and Normans had large trading areas over northern and western Europe, but the igneous and metamorphic rocks suggest that the Scandinavia and the Baltic region was a likely primary source. Kentish Rag This ragstone is a glauconitic green/brown sandy limestone from the Hythe Beds (Lower Greensand) of the Kent Weald. It was used as early as Roman times as building stone in London and is widespread in North Kent and the London Basin, but rare in Suffolk. The subject of Victorian fashion, it can be seen making the chancel of St Botolph’s, Iken, built in 1853 by architect John Whichcord of Maidstone, who had restored several other Kent churches; the patron and rector were also Kentish. The stone was evidently brought in by boat. St. Andrew’s, Melton built in 1868 by architect Fred Barnes of Ipswich, who also restored Kirton and Hemley churches, is another example. The stone was transported from source by rail. Septaria Calcareous mudstone concretions from the Eocene London Clay outcrop from Bawdsey southwards along the coast and up the Deben and Orwell estuaries on the foreshore. They were also obtained offshore by dredging, and were used at one time for the manufacture of Roman Cement. Impressions and borings by marine organisms can be seen in many church fabric septaria blocks and indicate their provenance. It is widely used in Suffolk’s Norman churches, and indeed appears to be the Norman’s ‘local stone of preference’, most often used in conjunction with Caen stone. The Leper Chapel, previously a Saxon church, is all that remains of St. James’ Hospital and with Greyfriars, is all that is left of the medieval city of Dunwich. Founded by Richard I at the end of the c. 12th, it was built outside the city itself for fear of the disease. Leprosy was ‘imported’, probably during the Crusades, because Dunwich was a thriving medieval port. The stylish Norman/Early English architecture can still be clearly seen, with fine carved Caen stone windows and arches. Of particular note, seen in the external north wall and internal east end, is the fine decorative contrast between imported pale Caen limestone and darker brown septaria, often over 30 cm across and badly weathered. There are many other examples of Norman and Medieval septaria churches – Orford (and Orford Castle), Iken, Falkenham, Kirton and Melton Old Church (which also contains the memorials and graves of geologists Searles Valentine Wood and his son) are just a few. Unfortunately, septaria fracture and weather easily and have been responsible for the crumbling and collapse of many structures, as the churches of Orford, Kirton, Bawdsey and, most dramatically, Alderton testify. Repair and restoration has been a constant theme! Boxstones The ‘boxstones’ are rounded pebbles of Miocene sandstone found in a discontinuous remanié deposit at the base of the Coralline and Red Crags in the areas around the Orwell and Deben rivers, and represent the only surviving remains of marine sediments of this age which were once deposited in the area. They are unique to Suffolk and north-east Essex.
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They were used in 1859 restoration of All Saints, Sutton, where they comprise 7–18% of the fabric. Many of the flints used here are also from the same basal deposit and clearly indicate a Red Crag provenance, being barnacle encrusted or with well-cemented Red Crag shells adhered to them, including Glycimeris, Spisula, Dosinia and Turritella. The flint and boxstone pebbles were evidently waste material from the mid-19th Century days of nearby ‘coprolite’ (phosphatic nodules) excavations, forming a cheap, readily available source of building stone.
Figure 1. Sutton church – Red Crag barnacles encrusting a flint from the Red Crag pebble bed. For the same reason, and from the same provenance boxstones can also be found in the fabric of Shottisham (with Red Crag barnacled flints, restored 1867) and Alderton (restored 1864) churches, and in the vestry at Melton (post-1868). All Saints, Waldringfield was restored in 1862 with money raised by the sale of coprolite from adjacent glebe, and the stained glass window at the east end of the chancel is known as ‘the coprolite window’. Coralline Crag This is a fossiliferous Pliocene shelly sand, which in places has been cemented to form a hard limestone, known as the Coralline Crag ‘Rock Bed’. This Crag is unique to Suffolk, outcropping from just north of Aldeburgh to Gedgrave with smaller inliers at Sutton, Ramsholt and Tattingstone. With the possible exception of Orford Castle, the ‘Rock Bed’ does not seem to have been used by the Normans, but mainly from the 14th–16th Centuries for lesser structures on farms and in walls (e.g. in Quay St and the churchyard at Orford) and for repair work, for example at Iken and Bawdsey.
18 More substantially, sawn blocks were used for an alteration to the nave and forming a buttress at St John Baptist, Butley; and a C15 extension to the chancel at All Saint’s, Eyke. Perhaps the best examples are to be found at St John Baptist, Wantisden and St Peter’s, Chillesford where the towers of churches were built of sawn blocks during the mid-14th Century. Blocks used for recent restoration at Chillesford came from Crag Farm, some 5 km to the east.
Figure 2. The Coralline Crag tower of Wantisden church.
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Figure 3. Dark Red Crag ironstone quoins at Ufford church. Red Crag This top-Pliocene shelly iron-stained sand outcrops widely over southern coastal Suffolk and northern Essex. As an unconsolidated sand, it is commonly used in mortar and can be found in many churches – look at the east end of the chancel of St Mary’s, Newbourne, where whole Astarte and large fragments of Cardium angustatum, Mya arenaria and other shells from a local pit can be seen. In some localities the Crag sand has been cemented by iron oxides to form an ironstone, often decalcified, and this has been used for building. At St Mary of the Assumption, Ufford, rough blocks can be seen in herringbone pattern courses in the north wall of the nave, forming quoins in the nave and elsewhere in the fabric; it seems likely that this is of Saxon origin. At All Saints, Eyke, on the south side of the chancel as much as 5–10% of the fabric is of Red Crag ironstone pebbles. And shelly Crag pebbles can be seen in St Ethelbert’s, Falkenham (another coprolite exporting village) and Newbourne church. Pulhamite ‘Pulhamite’ is an artificial stone named after James Pulham, born 1788, who specialised in ornamental, decorative plaster and cement items, such as heads,
20 garlands, fruit and foliage for buildings. He was apprenticed to William Lockwood, a prominent Woodbridge builder, businessman and pioneer of the cement industry, who made Roman & Portland cements at Lime Kiln Quay in Woodbridge. Pulham’s son, and later grandson and great grandson, developed the business to include making artificial rockeries over much of southern England, including those in Battersea Park, Waddesdon, Audely End and Sandringham.
Figure 4. The Pulhamite cliffs at Bawdsey Manor. At Bawdsey Manor the Pulhams laid out rockery gardens for Lady Quilter in 1896, creating meandering paths, tunnels and grottos covering the southern part of the cliff (the section was once described as the finest Red Crag exposure in England). The internal structure can be seen through weathered or vandalised ‘windows’ – a basic shape was created by blocks, bricks and rubble that was then overlain by patented Pulhamite cement, here containing small pebbles and many whelk shells. The finished effect is a gritty sandstone texture ‘rock’ forming realistic rocky crags with joints and bedding planes. Its remarkable durability is attributed to the great care taken in the mixing, pouring and sculpture of the material. This article is based on some of the work carried out for the “Suffolk GeoCoast Project”. Roger Dixon, The White House, 7 Chapel Street, Woodbridge IP12 4NF