Editing Flint (section)

===Ceramics===
Flint pebbles are used as the media in ball mills to grind glazes and other raw materials for the ceramics industry.<ref>{{cite book |title=Thoroughly Modern Milling |first=J.D. |last=Sawyer |series=American Ceramic Society Bulletin |volume=Bulletin&nbsp;86, No.&nbsp;6. |year=2007}}</ref> The pebbles are hand-selected based on colour; those having a tint of red, indicating high iron content, are discarded. The remaining blue-grey stones have a low content of [[chromophoric]] oxides and so are less deleterious to the colour of the ceramic composition after firing.<ref>{{cite book |title=Ceramics: Physical and chemical fundamentals |first1=H. |last1=Salmang |first2=M. |last2=Francis |publisher=Butterworths |year=1961}}</ref>

[[File:The name of the company on the site is now James Kent Limited. The three calcining ovens - formerly used for preparing flint for the ceramic industry are often known as 'salt, pepper and vinegar' by local people.jpg|thumb|Bottle kilns traditionally used for [[calcination|calcining]] flint]]
Until recently [[calcination|calcined]] flint was also an important raw material in clay-based [[ceramic]] bodies produced in the UK.<ref>{{cite book |title=Notes on the Manufacture of Earthenware |first=E.A. |last=Sandeman |publisher=The Technical Press Ltd. |year=1921}}</ref><ref name=Sugden-2001-IC-2>{{cite magazine |title=Changes & developments of non-plastic raw materials |last=Sugden |first=A. |magazine=International Ceramics |number=2 |year=2001}}</ref> In [[pottery|clay bodies]], calcined flint attenuates the shrinkage whilst drying, and modifies the fired thermal expansion.<ref>{{cite book |title=Whitewares: Production, testing, and quality control |first1=W. |last1=Ryan |first2=C. |last2=Radford |publisher=Pergamon Press |year=1987}}</ref> Flint can also be used in glazes as a network former.<ref>'Ceramics Glaze Technology.' Taylor J.R. & Bull A.C. The Institute Of Ceramics & Pergamon Press. 1986.</ref > In preparation for use flint pebbles, frequently sourced from the coasts of South-East England or Western France, were [[calcination|calcined]] to around {{cvt|1000|°C|-2}}. This heating process both removed organic impurities and induced certain physical reactions, including converting some of the quartz to [[cristobalite]]. After calcination the flint pebbles were crushed and milled to a fine particle size.<ref>{{cite book |title=Whitewares: Production, testing, and quality control |first1=W. |last1=Ryan |first2=C. |last2=Radford |publisher=Pergamon Press |year=1987}}</ref><ref>{{cite magazine |title=Use of flint in ceramics |magazine=Industrial Ceramics |number=885 |year=1993}}</ref><ref>{{cite magazine |title=Silica |first=Oelef |last=Heckroodt |magazine=Ceramic Review |number=254 |date=March–April 2012 |page=64}}</ref><ref>{{cite report |title=Calcination of Flint |first1=M. |last1=Manackerman |first2=E. |last2=Davies |series=Research Paper |volume=191 Part&nbsp;2: Continuous process in a vertical-shaft kiln |publisher=British Ceramic Research Association |year=1952}}</ref> However, the use of flint has now been superseded by [[quartz]].<ref name=Sugden-2001-IC-2/> Because of the historical use of flint, the word "flint" is used by some potters (especially in the U.S.) to refer generically to siliceous raw materials used in ceramics that are not flint.<ref>{{cite book |title=Ceramic Glazes |edition=3rd |last=Parmelee |first=C.W. |publisher=The Maple Press Company |year=1973}}<br/>{{cite book |title=Dictionary of Ceramics |edition=3rd |first=A. |last=Dodd |publisher=The Institute of Materials |year=1994}}<br/>{{cite book |title=The Potter's Dictionary of Materials and Techniques |first1=F. |last1=Hamer |first2=J. |last2=Hamer |place=London, UK |publisher=A. & C. Black |year=2004}}</ref><ref>{{cite conference |first=C.M. |last=Marsh |year=1978 |title=Flint and silica |book-title=Proceedings of the American Ceramic Society Annual Meeting 1978; Materials, Equipment, & Whitewares Division}}</ref><ref>{{cite magazine |title=Stoneware clay body formulas. Part&nbsp;2: The perfect body |first=J. |last=Zamek |magazine=Ceramics Industry |volume=155 |number=10 |year=2005}}</ref>