Totternhoe Stone is a relatively hard chalk

Chalk

Chalk is a soft, white, porous sedimentary rock, a form of limestone composed of the mineral calcite. Calcite is calcium carbonate or CaCO3. It forms under reasonably deep marine conditions from the gradual accumulation of minute calcite plates shed from micro-organisms called coccolithophores....

 outcropping in the middle of the Lower Chalk

Chalk Formation

The Chalk Group is a lithostratigraphic unit in the northwestern part of Europe. It is characterised by thick deposits of chalk, a soft porous white limestone, deposited in a marine environment during the Upper Cretaceous period.Chalk is a limestone that consists of coccolith biomicrite...

 in the Chiltern Hills

Chiltern Hills

The Chiltern Hills form a chalk escarpment in South East England. They are known locally as "the Chilterns". A large portion of the hills was designated officially as an Area of Outstanding Natural Beauty in 1965.-Location:...

 in Hertfordshire

Hertfordshire

Hertfordshire is a ceremonial and non-metropolitan county in the East region of England. The county town is Hertford.The county is one of the Home Counties and lies inland, bordered by Greater London , Buckinghamshire , Bedfordshire , Cambridgeshire and...

, Buckinghamshire

Buckinghamshire

Buckinghamshire is a ceremonial and non-metropolitan home county in South East England. The county town is Aylesbury, the largest town in the ceremonial county is Milton Keynes and largest town in the non-metropolitan county is High Wycombe....

, Bedfordshire

Bedfordshire

Bedfordshire is a ceremonial county of historic origin in England that forms part of the East of England region.It borders Cambridgeshire to the north-east, Northamptonshire to the north, Buckinghamshire to the west and Hertfordshire to the south-east....

 and Cambridgeshire

Cambridgeshire

Cambridgeshire is a county in England, bordering Lincolnshire to the north, Norfolk to the northeast, Suffolk to the east, Essex and Hertfordshire to the south, and Bedfordshire and Northamptonshire to the west...

, England

England

England is a country that is part of the United Kingdom. It shares land borders with Scotland to the north and Wales to the west; the Irish Sea is to the north west, the Celtic Sea to the south west, with the North Sea to the east and the English Channel to the south separating it from continental...

. Geologically, it is located in the upper part of the Cenomanian

Cenomanian

The Cenomanian is, in the ICS' geological timescale the oldest or earliest age of the Late Cretaceous epoch or the lowest stage of the Upper Cretaceous series. An age is a unit of geochronology: it is a unit of time; the stage is a unit in the stratigraphic column deposited during the corresponding...

 stage of the Cretaceous

Cretaceous

The Cretaceous , derived from the Latin "creta" , usually abbreviated K for its German translation Kreide , is a geologic period and system from circa to million years ago. In the geologic timescale, the Cretaceous follows the Jurassic period and is followed by the Paleogene period of the...

.

Unusually among chalks, it is sufficiently strong for use as a building stone, and has been used as such in these localities, notably in Woburn Abbey

Woburn Abbey

Woburn Abbey , near Woburn, Bedfordshire, England, is a country house, the seat of the Duke of Bedford and the location of the Woburn Safari Park.- Pre-20th century :...

, Luton parish church and several smaller local churches. It weathers rather badly in external use, but when used as internal carved decoration, it has remained in good condition for centuries. Old decorative carving is to be found in St Albans Abbey and in the altar screen of Westminster Abbey

Westminster Abbey

The Collegiate Church of St Peter at Westminster, popularly known as Westminster Abbey, is a large, mainly Gothic church, in the City of Westminster, London, United Kingdom, located just to the west of the Palace of Westminster. It is the traditional place of coronation and burial site for English,...

.

The Totternhoe Stone is underlain by the argillaceous

Argillaceous minerals

Argillaceous minerals may appear silvery upon optical reflection and are minerals containing substantial amounts of clay-like components . Argillaceous components are fine-grained aluminosilicates, and more particularly clay minerals such as kaolinite, montmorillonite-smectite, illite, and...

 Chalk Marl. Above is the less argillaceous Grey Chalk. The bed varies in thickness from 0.5 to 5 metres. The stone, although fine-grained, is siliceous, and partial cementing with silica accounts for its relative hardness. It forms a distinct escarpment at several locations at the base of the Chiltern ridge, notably at Totternhoe

Totternhoe

Totternhoe is a village and civil parish in the Manshead hundred of the county of Bedfordshire, England.-Overview:Totternhoe is an ancient village in southern Bedfordshire, near Dunstable and Leighton Buzzard. Totternhoe Knolls has been a fort for many peoples including Romans and Normans...

, Bedfordshire 51.89°N 0.576°W, where it is at its thickest. In addition to use as a building stone, in the past it was used in the manufacture of a hydraulic lime

Hydraulic lime

Hydraulic lime is a variety of lime, a slaked lime used to make lime mortar. Hydraulicity is the ability of lime to set under water. Hydraulic lime is produced by heating calcining limestone that contains clay and other impurities. Calcium reacts in the kiln with the clay minerals to produce...

, and in cement

Portland cement

Portland cement is the most common type of cement in general use around the world because it is a basic ingredient of concrete, mortar, stucco and most non-specialty grout...

 manufacture at three cement plants.

Quarrying

The stone has been quarried

Quarry

A quarry is a type of open-pit mine from which rock or minerals are extracted. Quarries are generally used for extracting building materials, such as dimension stone, construction aggregate, riprap, sand, and gravel. They are often collocated with concrete and asphalt plants due to the requirement...

 north of Totternhoe village in the county of Bedfordshire.

It was quarried at Totternhoe Knolls

Totternhoe Knolls

Totternhoe Knolls is a chalk hill, located north-west of Totternhoe village in the county of Bedfordshire, with the remains of a medieval castle. It is designated as a Site of Special Scientific Interest, as an example of chalk grassland....

, and to the east of the Knolls there were underground mines

Mining

Mining is the extraction of valuable minerals or other geological materials from the earth, from an ore body, vein or seam. The term also includes the removal of soil. Materials recovered by mining include base metals, precious metals, iron, uranium, coal, diamonds, limestone, oil shale, rock...

 for the stone. The area from where the medieval tunnels were dug is now designated a Site of Special Scientific Interest

Site of Special Scientific Interest

A Site of Special Scientific Interest is a conservation designation denoting a protected area in the United Kingdom. SSSIs are the basic building block of site-based nature conservation legislation and most other legal nature/geological conservation designations in Great Britain are based upon...

 (SSSI) called Totternhoe Chalk Quarry, as an example of chalk grassland

Calcareous grassland

Calcareous grassland is an ecosystem associated with thin basic soil, such as that on chalk and limestone downland. Plants on calcareous grassland are typically short and hardy, and include grasses and herbs such as clover...

. It is managed as a nature reserve

Nature reserve

A nature reserve is a protected area of importance for wildlife, flora, fauna or features of geological or other special interest, which is reserved and managed for conservation and to provide special opportunities for study or research...

 by the Wildlife Trust for Bedfordshire, Cambridgeshire, Northamptonshire and Peterborough

Wildlife Trust for Bedfordshire, Cambridgeshire, Northamptonshire and Peterborough

The Wildlife Trust for Bedfordshire, Cambridgeshire, Northamptonshire and Peterborough is a wildlife trust covering the counties of Bedfordshire, Cambridgeshire, Northamptonshire and the City of Peterborough in England....

.

In recent times the stone has been quarried in an area between the Knolls and the mines. This has been designated an SSSI called Totternhoe Stone Pit, as a Geological Conservation Review

Geological Conservation Review

The Geological Conservation Review is produced by the UK's Joint Nature Conservation Committee and is designed to identify those sites of national and international importance needed to show all the key scientific elements of the geological and geomorphological features of Britain...

 site.

The Stone is quarried by a family run business, H.G Clarke and Son. This was started in 1920 by Herbert G.Clarke. It was then passed to his son Stanley W.Clarke and is now being run by his son Angus J.Clarke. H.G Clarke and Son are the main suppliers of this rare English stone.

Further reading

• E. Roberts, "Totternhoe stone and flint in Hertfordshire churches", Medieval Archaeology, XVIII, 66-89, 1974.
• J. Curran, The Story of Totternhoe Quarries, Church End Publishing, 2005, OCLC 64310245.

External links

• Bedfordshire and Luton Geology Group, Totternhoe Stone.
• H.G Clarke and Son, Totternhoe – Clunch Stone.