Bembridge Limestones– NE Isle of Wight (Lead Author: WGT)
The Late Eocene to Early Oligocene limestones of the Binstead-Bembridge area were deposited 35-30 million years ago in freshwater environments, resulting in a range of rock types of limited extent. The Bembridge Limestone Formation (up to 9m thick) includes the Binstead Stone and the Quarr Stone*.
[NB: The Nettlestone Sandstone is a sandstone-siltstone in the underlying Headon Hill Formation. It can grade into a mouldic limestone similar to Quarr, but with characteristic fine cross-bedding]
[NB: The Nettlestone Sandstone is a sandstone-siltstone in the underlying Headon Hill Formation. It can grade into a mouldic limestone similar to Quarr, but with characteristic fine cross-bedding]
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Quarr Stone, also known as Featherbed Limestone or Featherstone. This cream to pale grey limestone was quarried between Quarr Abbey and Binstead to the end of the 14th century and mostly exported to the mainland. This was probably a lenticular deposit which was exhausted within 200 years. No exposures are known today but loose blocks can be found on the beaches. Quarr Stone is a cochina, a bivalve biosparite, originally a high density, low diversity, accumulation of small (<10mm) non-marine bivalves swept together by storm action. Some small gastropods are also present, as is sometimes lime mud and scattered quartz grains. It can be classed as a bioclastic grainstone-packstone.
Quarr vs Burr
Despite being about 110 million years younger, Quarr Stone is similar in appearance to the Lower Cretaceous Broken Shell Limestone (BSL) or Burr of the Purbeck Group (upper part of the Durlston Formation) and it is often hard to decide between them when examining a weathered building block encrusted with fungal/algal growth. Both are mouldic bivalve biosparite grainstones. This table may assist. 
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The Quarr Stone was probably a local basal bed of the Bembridge Limestone Formation which, elsewhere, has nodular shelly limestones at the base or, as suggested recently, was a bed just below the Bembridge Limestone*. Cross-bedding is sometimes seen in building blocks. Bioturbation is often visible and is very distinctive: shells were disturbed by organisms burrowing within the substrate, leaving shell-filled burrows 2-5 cm wide and up to 20cm long. During burial, the shells became lightly cemented by calcite and then the shells dissolved. Some resulting moulds were filled with sparite but many remain as voids, giving an overall tufaceous appearance (but not geological tufa).
Binstead Stone (also known as Bembridge Limestone, excluding Quarr)
This is a grey, dense, shelly lime packstone-wackestone, extensively quarried as building stone in the Quarr – Binstead area and known as Bembridge Limestone when extracted from beach ledges in the Bembridge area (recent Piddock borings can indicate this in building blocks). The freshwater gastropod Galba sp. is often seen. This micritic limestone is often vuggy (cavities) and concretionary, with minor amounts of very fine sand to silt grade quartz grains. 
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References
1847 Mantell – Geological Excursions to the Isle of Wight (a book)
1965 Anderson & Quirk – Note on the Quarr Stone. Mediaeval Archaeology vol 8, 1965 pp.115-117 (Appendix to Jope 1964)
2011 Lott – The Use of Local Stone in the Buildings of the Isle of Wight. Proc Geol Assoc 122 (2011) 923–932
2016 King – Strategic Stone Study: A Building Stone Atlas of the Isle of Wight. Historic England
*2016 Parker – Winchester Stone https://www.winchester-cathedral.org.uk/wp-content/uploads/Winchester-Stone.pdf
WGT March & Sept 2017
1847 Mantell – Geological Excursions to the Isle of Wight (a book)
1965 Anderson & Quirk – Note on the Quarr Stone. Mediaeval Archaeology vol 8, 1965 pp.115-117 (Appendix to Jope 1964)
2011 Lott – The Use of Local Stone in the Buildings of the Isle of Wight. Proc Geol Assoc 122 (2011) 923–932
2016 King – Strategic Stone Study: A Building Stone Atlas of the Isle of Wight. Historic England
*2016 Parker – Winchester Stone https://www.winchester-cathedral.org.uk/wp-content/uploads/Winchester-Stone.pdf
WGT March & Sept 2017
*Extract from: Parker 2016 pages 31-32
Quarr
I am indebted to Professor Andy Gale of Portsmouth University for the following account. It was originally thought that the stone from the Binstead quarries occurred as a lens within the (earliest Oligocene) Bembridge Limestone, a wider extending geological unit which is found across the north of the Isle of Wight from Yarmouth in the west to Bembridge in the east. Typically the Bembridge Limestone contains abundant largely entire shells of freshwater molluscs and this can be seen in the outcrops along the coast near Bembridge though this is not representative of the stone quarried for building at Binstead.
The Binstead stone has now been shown to be from a unit called the Seagrove Bay Member [Headon Hill Formation], which underlies the Bembridge Limestone Formation. This unit, which occurs as channel fills, is usually a sand, full of voids after comminuted freshwater gastropod shells. Locally, as at Binstead, it is a limestone with voids after aragonitic shell fragments, cemented by fine calcite spar and containing small rounded pieces of bone (distinctive in thin section).
Early exploitation of the Binstead quarries began in Roman times (2nd or early 3rd centuries, being used in the construction of Portchester Castle) and reached its peak in the Norman period. Quarrying was concentrated in a single limestone lens (the Featherbed), developed in the centre of Binstead, a mappable oval area some 400 metres by 200 metres in extent.. As the bed is only 60-70 cm thick, it was a limited resource and had been worked out by early medieval times, though it was noted by Gideon Mantell (who first described Iguanodon) in 1847. None of the original workings can be seen today.
The use of the term Quarr stone is unfortunate as Quarr is a different place to Binstead, and stone was never worked there. Bembridge Limestone was probably available near Binstead, but most likely was obtained from the extensive shore quarries at St Helens. It was not a popular material in the early mediaeval period but was used very extensively in Southampton, for example, the beautifully cut arches in the 14th century walls.
Quarr
I am indebted to Professor Andy Gale of Portsmouth University for the following account. It was originally thought that the stone from the Binstead quarries occurred as a lens within the (earliest Oligocene) Bembridge Limestone, a wider extending geological unit which is found across the north of the Isle of Wight from Yarmouth in the west to Bembridge in the east. Typically the Bembridge Limestone contains abundant largely entire shells of freshwater molluscs and this can be seen in the outcrops along the coast near Bembridge though this is not representative of the stone quarried for building at Binstead.
The Binstead stone has now been shown to be from a unit called the Seagrove Bay Member [Headon Hill Formation], which underlies the Bembridge Limestone Formation. This unit, which occurs as channel fills, is usually a sand, full of voids after comminuted freshwater gastropod shells. Locally, as at Binstead, it is a limestone with voids after aragonitic shell fragments, cemented by fine calcite spar and containing small rounded pieces of bone (distinctive in thin section).
Early exploitation of the Binstead quarries began in Roman times (2nd or early 3rd centuries, being used in the construction of Portchester Castle) and reached its peak in the Norman period. Quarrying was concentrated in a single limestone lens (the Featherbed), developed in the centre of Binstead, a mappable oval area some 400 metres by 200 metres in extent.. As the bed is only 60-70 cm thick, it was a limited resource and had been worked out by early medieval times, though it was noted by Gideon Mantell (who first described Iguanodon) in 1847. None of the original workings can be seen today.
The use of the term Quarr stone is unfortunate as Quarr is a different place to Binstead, and stone was never worked there. Bembridge Limestone was probably available near Binstead, but most likely was obtained from the extensive shore quarries at St Helens. It was not a popular material in the early mediaeval period but was used very extensively in Southampton, for example, the beautifully cut arches in the 14th century walls.
