China stone

Life size china clay sculptures outside the Wheal Martyn China Clay Museum, St Austell

China stone or "china clay" is a medium grained, feldspar-rich partially kaolinised granite characterized by the absence of iron-bearing minerals.[1] It is mainly used for making porcelain, hence the name, and coatings for paper. Its discovery in the 18th century was a crucial event in the development of the English porcelain industry. Its mineral content includes quartz, feldspar and mica; accessory minerals include kaolinite and fluorspar. It is found in one area of Cornwall in the United Kingdom, near St Austell, and is the UK’s only indigenous source of feldspathic material currently being commercially extracted, by English China Clays Plc. Production levels in the four years up to 2003 averaged 2,800 tonnes per year.[1]

Other names include Cornish or Cornwall stone.[2] It is sometimes confused with petuntse or "porcelain stone", which although somewhat similar, is a different rock.

References

  1. 1 2 Cornwall County Council website, China clay and china stone undated, URL retrieved on 14 September 2007
  2. ↑ Ceramic Materials Database undated, URL retrieved on 14 September 2007
This article is issued from Wikipedia - version of the 9/22/2016. The text is available under the Creative Commons Attribution/Share Alike but additional terms may apply for the media files.