During 2020-21 volunteers from the Tysoe Heritage Research Group (THRG) undertook a detailed survey of the memorials in both St Mary’s churchyard and in the extension cemetery in Sandpits Road. As well as recording names, dates, inscriptions and styles the survey noted the geology of the stones. Memorials offer a first-hand opportunity to observe rocks quarried from the wider world, particularly from the 19th century onwards as global transport links and stone carving techniques improved. The study of the rocks chosen for making memorials gives an insight into status, fashion, technology and even climate change, as well as bringing examples of remote geological sources into our local environment.
To include the range of gravestone geology this GEOLOGY TRAIL takes in both St Mary’s and Sandpits Road graveyards. We hope to stimulate your interest in the way stones are identified, their uses and properties.
Thanks
These notes have been produced with the generous help of Dr Nina Morgan and Dr Phillip Powell who kindly led members of the Tysoe Heritage Research Group in identifying the geology of the gravestones in the churchyard and in Sandpits Road cemetery, and who earmarked examples for comparison.
Any errors are of course mine.
David Freke 2022
Geological Identification
This informal note is intended to assist in the identification of the rock types used in the two Tysoe burial grounds: the churchyard and the Sandpits Road cemetery. The Geology Trail is intended as a guide through the three main geological groups: sedimentary, metamorphic and igneous.
Sedimentary rocks are formed by the deposition and mineralisation of materials such as mud and sand or the accumulation of calcium carbonate, to form mudstones, sandstones, conglomerates and limestones. Metamorphic rocks are the result of the action of heat and pressure on sedimentary rock to form marbles or slates. Igneous rocks have solidified from molten material from the earth’s interior to form granites, lava and basalts.
The majority of St Mary’s churchyard memorials are carved from sedimentary rocks, but a great variety of igneous rocks can be seen in the more recent memorials in the Sandpits Road cemetery, so it is useful to visit both sites.
The descriptions given here are of general geological types, sometimes they include geographical sources, but rarely identify actual quarry sites. The use of a x10 hand lens is recommended for many identifications, as is the scrutiny of lichen-free surfaces, preferably fresh breaks. A smart phone camera with a macro lens, used at maximum magnification, can also often give a good detailed view. All the close-up photographs in this note were taken this way. On no account, should stones be damaged or lichen removed.
Included here are plans of both Tysoe burial grounds, indicating memorials which are examples of rock types for comparison. Numbers in brackets are the Memorial Survey reference numbers should anyone wish to follow up the full details of the monuments (see THRG website: https://tysoehistory.org.uk).
Sedimentary Rocks: Limestones, sandstones, mudstones.
Limestones. Limestones are formed from the precipitation of calcium carbonate from water – the “limescale” found in kettles – or the accumulation of the calcium carbonate shells of millions of tiny marine organisms. Local limestones make up the Cotswolds, both the iron rich marlstones around Banbury and the oolitic limestones (ooliths are tiny calcium carbonate spheroids looking like cods-roe) to the south and west. Both are good building stones, and can be elaborately carved as gravestones, although they are susceptible to erosion. Softer Lias limestone forms the hills across the Feldon, and although commonly used elsewhere in Warwickshire for gravestones it erodes badly, and only one memorial 2 in Tysoe makes use of it. The local red-brown limestone (variously known as Banbury Stone, Hornton Stone or Marlstone) is used for almost all pre-19th century gravestones in Tysoe. Later memorials use a range of limestones from the midlands and further afield.
1 Portland Stone
The massive casket-shaped monument (380) by the west gate of the churchyard is made of Portland stone, with fossil oyster shells clearly visible. It is Upper Jurassic limestone, laid down in warm agitated seas 145 million years ago. Quarried in Dorset, it is white when clean, made of ooliths and occasional fossil oyster shells.
Below: detail of oyster shells standing proud of the weathered surface
Under the hand lens it looks like semolina. It is famous as the stone used to build St Paul’s in London after the Great Fire, and in the 20th century for Commonwealth War Graves (see Trail nos. 20 and 21 in the Sandpits Road cemetery).
2 White/Grey Lias limestone
This is a pale creamy-grey, fairly soft rock, made of limestone precipitated from a warm shallow sea around 205 million years ago. It forms the undulating hills of the area known as the Feldon south and east of the Avon, and is the common building stone in many Feldon villages.
This elaborate memorial (372) near the south west corner of the tower has elements made of White Lias. Other churchyards in the Feldon have many White Lias gravestones (eg Alveston Old Church), but the rock weathers very badly and is not often used where a harder alternative is available.
Blue Lias Limestone. This is mentioned here basically to exclude it from the list of rocks used in Tysoe graveyards; it is a soft blue/grey limestone which weathers even more than White Lias. Together with the White Lias Limestone it can be seen in many Feldon village buildings, for instance in Kineton, and it is the basis of the Rugby cement industry.
3 & 4 Guiting Stone
Part of the Inferior Oolite Group of the Jurassic Period, Guiting limestone occurs as two types: yellow, a warm brown to yellow-orange; and white, which can grade to dark cream. It is a hard, medium grained fossiliferous, oolitic limestone, moderate to poorly sorted. It has a rough feel, sometimes with prominent current-bedding. The church porch door has Yellow Guiting capitals, and the top stage of the tower is also Yellow Guiting. The south aisle parapet is White Guiting. The modern replacements of some pinnacles on the south aisle are the orangey colour of some contemporary Yellow Guiting beds. There are no gravestones of this material.
Left:3 Yellow Guiting Porch capitals and 4 White Guiting, South aisle parapet,
Below right: Early 20th-century repair to nave pinnacle showing ooliths and shell fragments
5 Banbury Stone/Hornton Stone /Marlstone
These are the common names for the iron-rich strata of the Middle Lias Group of the early Jurassic Periods (195 -170 million years old). The colour ranges from pale buff to deep brown or dark greeny-blue, but generally a reddish brown. It was laid down in a warm shallow sea near a well-vegetated landmass, the source of the iron. It contains bivalve and brachiopod fossils, frequent belemnites, crushed shells, sand and some ooliths
The iron frequently appears as irregular veins meandering through the stone. These iron veins and fossils are characteristic of this rock. It is relatively easy to work, but erodes under weathering. The escarpment above the village is composed of this rock, and many village houses, as well as most of the early phases of the church, were probably built using stone from local quarries. All the early headstones in the churchyard are made of this local rock, often deeply carved, depending upon the style of the period.
Right: Belemnite fossil in Hornton Stone in St Mary’s church porch
6 Taynton Stone
Taynton Stone is a Cotswolds limestone from the Great Oolite Group of the Middle Jurassic Period formed around 167 million years ago. It was laid down in a tropical sea. It is oolitic (containing small spherical grains of limestone, formed around specks of sand); it includes fossil fragments of corals, oysters, and other shellfish. It is white to pale brown, coarse to fine grained, with bands of different hardness, some cross bedded, often exposed through erosion. Some beds around Stonesfield can be split to form “Stonesfield Slate”, the characteristic stone roof-tiles of the Cotswolds. Taynton Stone has been quarried for building stone for centuries. It has not been used for gravestones in Tysoe but the medieval churchyard cross shaft and plinth are probably Taynton stone.
7 Nabresina Limestone
This is the trade name for limestone from quarries in Zolla near Trieste, Italy. It is the hardest commercially available limestone and has become popular for gravestones, and also for cremation plaques. Under a hand lens one can see numerous glassy shell fragments in a dense white matrix. It has a homogenous texture lacking large fossils, so is ideal for fine inscriptions.
Right: detail showing copious fragmentary fossils in dense white
Sandstones
Sandstones are composed of sand-sized grains, often quartz, accumulated in water or deserts, cemented together by minerals precipitated from groundwater. Many minerals may be present. There several sources of sandstones in the Warwickshire area. The oldest is the Coal Measures Sandstone, formed 326-311 million years ago. This is a pale buff-grey sandstone. The red Coventry Sandstone from the Upper Carboniferous, was laid down 310 – 290 million years ago. The reddish Kenilworth Sandstone of the Permian Period, was formed around 290 to 270 million years ago. These rocks appear to have been rarely used as gravestones in Tysoe. Without detailed petrological examination some sandstones in Tysoe can only be categorised as “Grey” or “Red/Pink” although Bromsgrove and Pennant Sandstones can sometimes be identified.
8 Pennant Sandstone
Right: splitting and flaking
Laid down in the Upper Carboniferous Period, around 313 million years ago, Pennant Sandstone comes from the Forest of Dean and South Wales. It is pale to mid -grey, made of angular and rounded quartz grains, with white or pinkish feldspar, flakes of mica and dull black specks of coal. It is hard and durable, but can split or flake if water has found a weakness. It became popular for gravestones in the 19th century when transport became cheaper.
9 Grey Sandstone – Bromsgrove?
Warwick Castle (and much of Warwick itself) is built on, and constructed of, the buff-grey Bromsgrove Sandstone, also known as Warwick Sandstone, quarried at Coton End. This is 240–225 million years old, laid down as sands and mud in river channels and deltas. There are some possible candidates made of this rock in the churchyard.
It can spall (surface flaking from freeze-thaw episodes), as can be seen on Memorial 265 to the wife of Thomas Goodwin. The style of this headstone dates it to the later part of the 19th or early 20th century. It is now virtually unreadable after about 150 years, whereas many Hornton stone memorials of the 18th, or even the 17th century remain legible.
10 Grey Sandstones
The churchyard contains a scattering of headstones made of fine-grained grey sandstones. These are difficult to identify without detailed examination, but could be from the Coal Measures beds in the north of the county, or, like the Pennant Sandstones, from sources further afield.
Memorial (225) is an example, and shows the detailed carving possible on some of these rock types. Its date of 1915 is typical of the period when these harder rocks became increasingly accessible and more popular, while not being as expensive as the continental marbles.
There are some examples of yellow and pink sandstones in the Sandpits Road cemetery, eg Trail nos. 23 and 24 Memorials (1134 and 1129).
Metamorphic Rocks.
Metamorphic rocks started out as sedimentary sandstones, mudstones or limestones, but which were then subjected to heat and pressure in the course of geological upheavals. Italian marbles for instance were formed from limestones crushed as the Alps were forced up by Africa crashing into Europe. Sandstones and mudstones can be transformed into slates by similar forces, like the Lake District slates, originally the ash from volcanic eruptions, heated and compressed by subsequent seismic activity.
11 Lake District Slate
The hardness and fine grain of some slatesmake them attractive rocks for detailed carving and fine calligraphy. The nearest slate quarries in Leicestershire are too distant for them to be commonly used as gravestones in Tysoe before cheap canal and rail transport made them more accessible. Slate memorials of any date are relatively rare in south Warwickshire, and early examples indicate high status burials.
The slate used for 11 Memorial (130), was formed of the ash from submerged volcanic eruptions in the Ordovician Period about 450 million years ago. The rear shows evidence of successive eruptions as diagonal layers of ash grading from coarser to finer. The stone is inverted from its original stratigraphic disposition.
12 Carrara Marble
A hard white stone from Italy, formed at the beginning of the Jurassic Period 200 million years ago. It was created when limestone was compressed and heated causing the calcium carbonate to form crystalline grains. Marble from Carrara is commonly used for gravestones; seen under a hand lens it has a texture like granulated sugar, marble from other sources can look like castor-sugar. Minerals such as iron can introduce coloured veins. Marble takes a fine polish but when weathered it can be dull and grey-blue in colour. To identify it, look for corners or areas rubbed or broken, and free of lichens.
13 Marble
14 Marble
Memorial (22) demonstrates the sculptural qualities of this material, in the realistic depiction of a tree stump (symbolising life cut short) in the form of a cross (Christ’s sacrifice) wreathed in flowers (poppies symbolising sleep and Christ’s passion; roses symbolising love, and tulips symbolising the afterlife).
Igneous Rocks
Igneous rocks are formed when molten magma cools and solidifies either underground (intrusive) or at the earth’s surface from volcanoes (extrusive). Slow-cooling intrusive rocks, solidifying deep underground, have larger crystals, usually visible to the naked eye, as in many granites. The crystals become smaller the quicker the cooling process. Rapidly cooled extrusive rocks such as basalt have a glassy texture. Gabbro is similar to granite, often with a visible crystalline structure, but it does not contain quartz. Both granite and gabbro are found as gravestones in Tysoe. They are very hard rocks, only becoming popular for gravestones when transport and power tools made obtaining and carving them an economic proposition.
15 & 16 Cornish Granite
Available granites occur where earth movements and erosion have exposed the previously buried masses; in the British Isles they are quarried in Cornwall, Devon, Cumbria, Wales and Scotland. Cornish granite gravestones tend to be grey, with sparkling mica flecks, and large crystals. Trail numbers 15 and 16 Memorials (23) and (24) show the differences in texture of the same Cornish granite, polished and unpolished. More recent grey granites may come from Scandinavian sources.
Sandpits Road Cemetery Geology Trail
In the 20th century, like many small country church graveyards, St Mary’s churchyard became unable to accommodate the burials from the growing population of the village. This, coupled with the larger footprint of the memorials commissioned by clients, and the diversity of religious practice, led to the extension in Sandpits Road, opened in the 1930s. It is noticeable how many memorials here have kerbs, amounting to half of the 240 monuments, and the styles of the gravestones are also much more diverse than those in St Mary’s churchyard. Geologically the stones are also more diverse, made of rocks from around the world. The trail is arranged like the St Mary’s one, to progress from sedimentary through metamorphic to igneous rocks.
The description of the geology of St Mary’s churchyard should be consulted for further details to help in the identification of the rocks at the Sandpits Road cemetery.
17, 18 & 19 Banbury Stone/Hornton Stone/Marlstone
Unlike gravestones in St Mary’s churchyard, here only a few are made of the local Hornton Stone. The three most imposing examples are grouped together in the north-east corner (Memorials 1238, 1239, 1240). The choice of local stone at a time when exotic foreign materials were more fashionable, together with the traditional headstone design, are indications of the impression the clients wanted to project. The inscriptions are equally telling.
20 Banbury Stone/Hornton Stone/Marlstone
Right: detail of fossil shell bed
Trail no. 20 is an example of the kerbed memorials which began to appear at the end of the 19th century and were popular for much of the 20th century.
21 & 22 Portland Stone
These are headstones made of the white Portland Stone used by the Commonwealth War Graves commission for the memorials of the fallen in the two World Wars.
The fossil oyster shell fragments characteristic of this stone can be clearly seen on the reverse of 22. where the original polished surface has been etched away by acid rain to leave them in relief. There are research projects which measure the depth of this type of erosion to monitor the effects of climate change, using the date of the stone as a convenient indication of time elapsed.
23 Pennant Sandstone
This dense fine-grained grey sandstone comes from the Forest of Dean and South Wales, and allows for fine detailed carving. The transport improvements in the 19th and 20th centuries made it a preferred option over the local ironstone, although it is rarely carved as exuberantly or as freely as 18th century masons contrived with the local material. The more recent period opened up sources unthinkable to earlier stone workers but it it was also a period of mechanical and formulaic styles.
24 Red/ Pink Sandstone (Kenilworth?)
Beneath the lichens and erosion this is a pinkish coarse grained sandstone, possibly from the Permian Kenilworth Sandstone Formation, laid down in rivers around 297 million years ago. There are few examples of this stone in Tysoe. cemeteries. It is an easily worked building stone.
Kenilworth Castle and the Abbey ruins are examples of its use. It does, however, erode badly.
25 & 26 Marble
Marble is a common material in this cemetery, used both for kerbs, as shown in 25 Memorial (1132) and for sculptural effects, as seen on 26 Memorial (1107).
The sculptured angel on 26 has been damaged, but the broken portions give a fresh surface to view the crystalline structure of unpolished marble, not from Carrara, looking like caster sugar under a hand lens.
27 Grey Granite
This large kerb memorial, with accommodation for three, is made of (possibly) Cornish granite, although by the 1980s Scandinavian grey granite was available. The stone has been left unpolished, to bring out the uncompromisingly rugged nature of the stone, and also possibly the character of the clients.
28 Pink/Red Granite
Pink granite from Peterhead was popular in the 19th century but more recently pink/red granites have come from Scandinavia. Pink granite is sometimes misleadingly called “Balmoral Granite” because the castle there is constructed of it. 28, Memorial (1137) has a local mason’s name – Cakebread of Banbury – but intriguingly no other inscription.
29 Gabbro
Gabbro is commercially known as “black granite” though it is not strictly a granite as it contains less quartz. It can be very dark grey/black or a paler grey, depending upon the proportions of dark mineral crystals and pale feldspar. It is very hard and difficult to work, however modern cutting tools together with etching and polishing can bring out striking graphic qualities, and many memorials in the Sandpits Road cemetery show these effects.
Sources of further Information:
This note was inspired by Dr Nina Morgan and Dr Phillip Powell and their invaluable book The Geology of Oxford Gravestones, 2015.
Visit their website at: https://www.gravestonegeology.uk/
Other useful sources are:
Historic England Strategic Stone Study A Building Stone Atlas of Warwickshire, 2011;
British Regional Geology Central England, 3rd ed. 1969;
Ladbroke Churchyard Geology leaflet, u/d;
Warwickshire Wildlife Trust and Warwickshire Geological Conservation Group leaflet Every Stone Tells a Story, available online at https://www.wgcg.co.uk/guides/leaflets/
Wendy Kirk and David Cook, Graveyard Geology: a guide to rocks in Graveyards and Cemeteries u/d, available online at
earth_sciences_geotrail_graveyard_geology.pdf (ucl.ac.uk)
WGCG Brandon Wall: the rocks of Warwickshire as represented in the Geology Wall at Brandon Marsh available online at: Brandon Wall | Warwickshire Geological Conservation Group (WGCG)
