Portland stone

Portland stone

Portland stone is a limestone from the Jurassic period quarried on the Isle of Portland, Dorset. The quarries consist of beds of white-grey limestone separated by chert beds. It has been used extensively throughout the British Isles, notably in major public buildings in London such as St Paul's Cathedral and Buckingham Palace. It is also exported to many countries - Portland stone is used in the United Nations headquarters building in New York city, for example.

The term "Portland Cement" was coined by Joseph Aspdin who produced first in 1824 a hydraulic binder by burning a mixture of limestone and clay resembling the Roman cement and presenting a texture very close to that of the oolitic Portland stone. [cite encyclopedia
last = Gerhartz
first = W. (Ed.)
title = Cement and concrete: see p. 492
encyclopedia = In: Ullmann's Encyclopedia of Industrial Chemistry. Fifth completely revised edition,
volume = Volume A5
pages =
publisher = VCH Publisher, New York
date = 1986
id = ISBN 0-89573-155-X
accessdate =

]

All gravestones for British personnel killed in the First and Second World Wars are made out of Portland stone. However, these began to weather and detail such as the regimental badges were becoming difficult to view. The Commonwealth War Graves Commission began to use botticino, a white marble limestone, from about 1998. Portand stone was used for the £6 million memorial in Staffordshire, England, designed by Liam O'Connor Architects and Planning Consultants, that bears the names of over 16,000 service personnel who died since World War II [ [http://news.bbc.co.uk/2/hi/uk_news/7040801.stm BBC NEWS | UK | Queen unveils new forces memorial ] ] .

Three main "Portland Beds" are quarried. The Base and Portland Independent Top Whitbed beds are fine textured and contain few fossil remains, and so are popular for high quality work. The Portland Admiralty Roach bed is rougher with many fossils and its stone is notably used in the Cobb, at nearby Lyme Regis.

The [http://www.learningstone.org/ Portland Sculpture and Quarry Trust] was formed in 1983. The Trust is dedicated to preserving a knowledge and understanding of stone and the landscape from which it comes.

ee also

*List of stone
*List of types of limestone
*Portland Admiralty Roach
*Portland Bowers Basebed
*Portland Bowers Lynham Whitbed
*Portland Bowers Saunders Whitbed
*Portland Grove Whitbed
*Portland Hard Blue
*Portland Independent Basebed
*Portland Independent Bottom Whitbed
*Portland Independent Top Whitbed
*Portland New Independent Whitbed
*Portland cement

References

External links

* [http://www.jurassiccoast.com/index.jsp?articleid=26738 Geology of the Jurassic Coast]
* [http://web.ukonline.co.uk/conker/fossils/portland.htm Portland fossils]
* [http://www.bbc.co.uk/london/walks/lookandsee.shtml London buildings/stone]


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Look at other dictionaries:

  • Portland stone — Port land stone A yellowish white calcareous freestone from the Isle of Portland in England, much used in building. [1913 Webster] …   The Collaborative International Dictionary of English

  • portland stone — n. a limestone from the Isle of Portland in Dorset, used in building. * * * noun Etymology: from Isle of Portland, peninsula in southern England, its locality 1. usually capitalized P : a yellowish white oolitic building limestone 2. usually… …   Useful english dictionary

  • Portland stone — ➡ Portland cement * * * …   Universalium

  • Portland stone — noun limestone from the Isle of Portland in Dorset, valued as a building material …   English new terms dictionary

  • Portland stone — /pɔtlənd ˈstoʊn/ (say pawtluhnd stohn) noun a type of limestone, used in building. {quarried on the Isle of Portland, Dorset, England} …  

  • Portland — has many meanings. It is the name of numerous cities, the largest of which is Portland, Oregon, in the United States. The name originated with the Isle of Portland, in Dorset, United Kingdom. It applies to people, buildings, passenger trains,… …   Wikipedia

  • Portland cement — is the most common type of cement in general usage in many parts of the world, as it is a basic ingredient of concrete, mortar, stucco and most non specialty grout. It is a fine powder produced by Portland cement clinker (more than 90%), a… …   Wikipedia

  • Portland Bill — is a narrow promontory (or bill) of Portland stone, which forms the most southerly part of Isle of Portland, and therefore also the county of Dorset, England.The Bill is an important way point for coastal traffic, and so three lighthouses have… …   Wikipedia

  • Portland Independent Top Whitbed — is the variety of Portland stone used to build The Ashton Memorial in Lancaster. It originates from Independent quarries on the Isle of Portland, Dorset …   Wikipedia

  • Portland cement — Port land ce*ment A cement having the color of the Portland stone of England, made by calcining an artificial mixture of carbonate of lime and clay, or sometimes certain natural limestones or chalky clays. It contains a large proportion of clay,… …   The Collaborative International Dictionary of English

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