Crag Pit Farm is a classic Coralline Crag site notified as an SSSI. It is rich in Bryozoans, and well documented for wave-features in the sands. There are few other fossils, and the shell beds are much deeper down, but it is certainly a location to visit for anyone who is interested in Bryozoans.
♦ Crag Pit Farm is near Sudbourne in Suffolk. The pit is on a farm, and you will need permission from the farm owners to visit.
♦ The farm can be found to the South East of Sudbourne. It is shown under 1:25,000 scale maps, and on 1:50,000 scale it is marked as ‘Crag Farm’
♦ From Sudbourne, there are three exits from the village, take the Eastern exit, when you come to a junction, turn right, at the second junction, turn left and you will find Crag Farm.
♦ Ref: 52.11602°N, 1.54558°E
FIND FREQUENCY: ♦♦♦ – This site is rich in Bryozoans, you will certainly find some excellent specimens, but other fossils are not so common. Shells can occasionally be found, but the actual shell beds are much deeper and not exposed.
CHILDREN: ♦♦ – Quarries and pits either working or disused are no places for children as they present many dangers.
ACCESS: ♦♦♦ – Crag Pit Farm is easy to find, and the faces are kept clean as part of the SSSI Notification. If you drive up to Crag Pit Farm, and see the owners, they should allow access.
TYPE: – Fossils are found in the cliff face which is constantly being eroded by wind and rain. The pit floor is grassed over, but kept cut to make access easy. Please note, that digging is not permitted at this site, please only take one or two specimens.
Well-preserved, colonies of the bryozoans Eschara pertusa, are the most common find here, the site is well documented for this fossil, along with the spectacular round Bryozoans – Meandropora tubipora. When complete, these specimens are the size of tennis balls, occasionally if you find one broken, you will see all of the internal structure.
Shells and other fossils are rare at this site, as the beds are much deeper, although shells can occasionally be found such as scallops. To find fossils, search the cliff faces as these are regularly kept clean and constantly eroded by the wind and rain.
The pit at Crag Pit Farm is of Pliocene age being the Coralline Crag. This crag is made of carbonate-rich skeletal sands. The acid-insoluble sand fraction is moderately- to poorly-sorted medium-grained sand. It has a low mud content and the basal lag gravel is rich in pebbles of phosphatic mudstone largely derived from the Thames Group.
Crag Pit Farm is notified as an SSSI due to its geological importance, Faces of the pit afford the best available exposure in the Coralline Crags and wave facies. About 5m of crag is exposed showing well-defined, large-scale cross-stratification a set thickness of up to 2g m. Conspicuous calcite ‘veins’ are presentwhich may be related to diagenetic removal of aragonitic material during a sub-aerial solutional phase.
Although there are no major safety issues at this site, but please follow the country code. Please use common sense at all locations. Some of the faces could collapse at any moment, so please take care, and do not collect from the overhanging areas.
A trowel or knife should be used for removing the shells from the shell beds. Fossil shells are fragile, so paper, and specimen boxes should also be taken.
This site is an SSSI. This means you can visit the site, but hammering the bedrock is not permitted. For full information about the reasons for the status of the site and restrictions please download the PDF from Natural England – SSSI Information – Crag Pit Farm