Ajay Kumar at 17:03, 24 August 2023

2023-08-24T17:03:46Z

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{{Short description|Kaolinitic sedimentary clay}}
{{Use dmy dates|date=April 2022}}
'''Ball clays''' are [[kaolinite|kaolinitic]] [[sedimentary]] [[clay]]s that commonly consist of 20–80% [[kaolinite]], 10–25% [[mica]] and 6–65% [[quartz]], along with small amounts of organic matter (such as [[lignite]]) and trace amounts of other minerals such as [[pyrite]] and [[siderite]].

They are a common [[Industrial mineral|raw material]] for various types of ceramics, where their primary roles are to impart unfired strength, plasticity or to aid [[rheological]] stability during the shaping processes.<ref>'Ceramic Raw Materials' 2nd edition. W.E. Worrall. Pergamon Press, 1982</ref> Most ball clays impart colours ranging from buff to cream to off-white when fired in an oxidising atmosphere.<ref name="ReferenceA">'Industrial Minerals & Rocks - Commodities, Markets And Uses' J. E. Kogel. Society For Mining, Metallurgy And Exploration, 2006</ref><ref name="ima"/>

The name "ball clay" is derived from the form of the extracted material when dug by spade as cubes, which then became rounded during subsequent transport, in [[Devon|Devon, England]] during the early days of the industry during the [[18th century]].<ref>’Ball Clay Basics’ P. S. Powell. Ceram. Eng. Sci. Proc., 16 [3] 200-206, 1995. Pg. 200</ref><ref name="ima">{{cite web
|title = What is ball clay?
|publisher = Industrial Minerals Association - North America
|url = http://www.ima-na.org/ball-clay
|accessdate = 2008-08-05
|url-status = dead
|archiveurl = https://web.archive.org/web/20090923120805/http://www.ima-na.org/Ball-Clay
|archivedate = 2009-09-23
}}</ref>

In 2008, UK production of ball clay was reported to be worth £82 million, with sanitaryware manufacturers being the largest single group of end users, representing 40% by volume.<ref>‘Ball Clay’ Mineral Plannng Factsheet. British Geological Surkey. 2008.</ref> In 2022, the global market for ball clay was estimated to be worth $US375 million, with the Asia-Pacific region being the biggest market accounting for 38.2% of sales.<ref>‘Ball Clay Market.’ Coherent Market Insights Pvt Ltd. 2022</ref>

==Locations==
[[File:Track out of Newbridge ball clay quarry - geograph.org.uk - 1654782.jpg|thumb|A ball clay mine in the UK]]

They are relatively scarce deposits due to the combination of geological factors needed for their formation and preservation.<ref name="bgs">{{cite web
| last = Highley
| first = David
| authorlink =
|author2= Bloodworth, Andrew|author3= Bate, Richard
| title = Ball Clay - Mineral Planning Factsheet
| publisher = British Geological Survey
| date = 2006
| url = http://www.mineralsuk.com/britmin/mpfball_clay.pdf
| format = pdf file
| accessdate = 2008-08-05}}</ref> Commercial extraction of ball clays is undertaken across the world, including:<ref>’The Constitution, Evaluation And Ceramic Properties Of Ball Clays’ I. R. Wilson. Cerâmica vol.44 no.287-288 São Paulo May/June/July/Aug. 1998</ref>
*Argentina (San Julian area of Patagonia)
*Brazil (various locations including the region around São Paulo - São Simão, Suzano and Ribeirão Pire)
*China (various including Guangdong Province)
*Czech Republic (Cheb, Pilsen, Prague, Most, S. Bohemia and W. Moravia)
*Germany (various locations but the main is the Westerwald region)
*Indonesia (various locations including the island of Kalimantan)
*Thailand (Lampang)
*United Kingdom (the Bovey Basin of south Devon, the Petrockstow Basin in north Devon and the area around Wareham in south-east Dorset)
*USA (Kenthcky, Tennessee and Texas)

==Production output==
Global production of ball clay by country for 2002-2003 was estimated to be:<ref name="ReferenceA"/>
{| class="wikitable collapsible"
!Country
!1,000 tonnes
|-
|[[South Africa]]
|10
|-
|'''Africa''' - total
|10
|-
|
|
|-
|[[China]]
|2,000
|-
|[[Malaysia]]
|600
|-
|[[Indonesia]]
|500
|-
|[[Thailand]]
|300
|-
|[[Vietnam]]
|200
|-
|[[India]]
|150
|-
|'''Asia''' - total
|3,750
|-
|
|
|-
|[[Ukraine]]
|3,500
|-
|[[Germany]]
|3,000
|-
|[[Spain]]
|1,200
|-
|[[United Kingdom]]
|1,000
|-
|[[Turkey]]
|550
|-
|[[Czech Republic]]
|400
|-
|[[France]]
|400
|-
|[[Italy]]
|100
|-
|[[Poland]]
|50
|-
|'''Europe''' - total
|10,200
|-
|
|
|-
|United States
|1,200
|-
|'''North America''' - total
|1,200
|-
|
|
|-
|[[Australia]]
|80
|-
|'''Oceania''' - total
|80
|-
|
|
|-
|[[Brazil]]
|250
|-
|[[Argentia]]
|50
|-
|[[Chile]]
|5
|-
|'''South America''' - total
|350
|-
|
|
|-
|'''Global''' - total
|15,385
|}

==Typical properties==
Some selected typical properties of various UK ball clays are:<ref name="ReferenceA"/>

{| class="wikitable collapsible"
! Product name !! Hycast Rapide !! Sanblend 75 Slurry !! Prestige BLU !! Prestige TA !! Hyplas 71 !! Hymod Excelsior !! Hymod Blue
|-
! Source
| Bovey || Bovey || Bovey || Petrockstow || Petrockstow || Wareham || Warehan
|-
! Producing company
| Imerys || WBB || WBB || WBB || Imerys || Imerys || Imerys
|-
!
| || || || || || ||
|-
! Residue, wt% <125 µm
| 2.0 || 0.1 || 0.2 || 0.5 || 1.0 || 0.3 || 0.1
|-
! % <2 µm
| 70 || 78 || 82 || 77 || 57 || 92 || 89
|-
! % <1 µm
| 60 || 65 || -|| -|| 50 || 87 || 79
|-
! % <0.5 µm
| 45 || -|| -|| -|| 40 || 80 || 65
|-
!
| || || || || || ||
|-
! SiO2, %
| 55.0 || 53.7 || 54.0 || 60.5 || 69.0 || 49.0 || 53.0
|-
! Al2O3, %
| 29.0 || 28.9 || 31.2 || 25.8 || 20.0 || 35.0 || 31.0
|-
! Fe2O3, %
| 1.1 || 1.2 || 1.0 || 1.9 || 0.9 || 1.6 || 1.4
|-
! TiO2, %
| 1.1 || 1.1 || 1.2 || 1.5 || 1.7 || 1.3 || 1.0
|-
! CaO, %
| 0.2 || -|| -|| -|| 0.1 || 0.3 || 0.3
|-
! MgO, %
| 0.3 || -|| -|| -|| 0.4 || 0.3 || 0.5
|-
! K2O, %
| 1.6 || 2.5 || 3.0 || 2.9 || 1.9 || 1.2 || 3.2
|-
! Na2O, %
| 0.2 || -|| -|| -|| 0.4 || 0.2 || 0.4
|-
! Carbon, %
| 2.0 || 2.5 || 0.2 || 0.6 || 0.1 || 0.3 || 0.4
|-
! LOI, %
| 12.0 || 12.0 || 9.0 || 8.0 || 5.4 || 12.0 || 9.2
|}

==History in the UK==
The [[ceramic]] use of ball clays in [[Great Britain|Britain]] dates back to at least the [[Roman Empire|Roman]] era. More recent trade began when a clay was needed to make [[Smoking pipe (tobacco)|tobacco pipes]] in the 16th and 17th century.<ref name="bchs">{{cite web
| title = The Widespread Use of Ball Clay
| work = Introduction to Ball Clays
| publisher = The Ball Clay Heritage Society
| url = http://www.clayheritage.org/pages/wideuses.htm
| accessdate = 2008-08-05
| archive-url = https://web.archive.org/web/20081006163547/http://www.clayheritage.org/pages/wideuses.htm
| archive-date = 2008-10-06
| url-status = dead
}}</ref> In 1771 [[Josiah Wedgwood]] signed a contract for 1,400 tons a year of ball clay with Thomas Hyde of [[Isle of Purbeck|Purbeck]], enabling the production of thinner-walled ceramics.<ref name="purb">{{cite web
|title = History of Ball Clay - Swanage Railway
|publisher = The Purbeck Mineral & Mining Museum
|url = http://www.pmmmg.org/History.htm
|accessdate = 2008-08-05
|archive-url = https://web.archive.org/web/20080514210942/http://www.pmmmg.org/History.htm
|archive-date = 2008-05-14
|url-status = dead
}}</ref>

==See also==
*[[Newton Abbot#Ball clay and the Stover Canal|Ball clay and the Stover Canal]]
*[[Purbeck Ball Clay]]

== References ==
{{Reflist|colwidth=35em}}

{{Pottery}}

[[Category:Pottery]]
[[Category:Geology of Devon]]
[[Category:Clay]]
[[Category:Industrial minerals]]

Ball clay - Revision history

Ajay Kumar at 17:03, 24 August 2023