Temper (pottery)

Prevents shrinkage and cracking of clay

A temper is a non-plastic material added to clay to prevent shrinkage and cracking during drying and firing of vessels made from the clay.[1] Tempers may include:

* Bone;[2]
* Chaff;[2]
* Charcoal;[3]
* Ground schist;[4]
* Wood ash;[5]
* Grit;[1]
* Sand or crushed sandstone;[6]
* Crushed limestone;[7]
* Crushed igneous rocks, such as volcanic rock, feldspar, or mica;[5][8][9]
* Grog;[6]
* Plant fiber;[10]
* Horse manure (dried and sifted);[11]
* Crushed mollusc shells (including fossilized)[1][7] (see Shell tempering in the Mississippian culture); and
* Freshwater sponge spicules.[5][12][13]

Some clays used to make pottery do not require the addition of tempers. Pure kaolin clay does not require tempering.[6] Some clays are self-tempered, that is, naturally contain enough mica, sand, or sponge spicules that they do not require additional tempering.[14][13]

## See also

[edit]

Ceramic#Archaeology

## Citations

[edit]

1. ^ a b c "Ceramics". Mississippi Valley Archaeology Center – Technologies. University of Wisconsin – La Crosse. Archived from the original on 27 September 2011. Retrieved 4 November 2011.
2. ^ a b Stilborg, Ole (1 December 2001). "Temper for the Sake of Coherence: Analyses of Bone- and Chaff-Tempered Ceramics from Iron Age Scandinavia". European Journal of Archaeology. 4 (3). Maney Publishing: 398–404. doi:10.1177/146195710100400316. ISSN 1461-9571.
3. ^ Silverman & Isbell 2008, p. 439.
4. ^ Fontana, Bernard L.; Robinson, William J.; Cormack, Charles W.; Leavitt, Earnest E. (1962). Papago Indian Pottery. Seattle, Washington: University of Washington Press, on behalf of the American Ethnological Society. p. 57\. OCLC 869680.
5. ^ a b c Marcondes Lima da Costa; Dirse Clara Kern; Alice Helena Eleotério Pinto; Jorge Raimundo da Trindade Souza (2004). "The ceramic artifacts in archaeological black earth (terra preta) from lower Amazon region, Brazil: Mineralogy". Acta Amazonica. 34 (2): 165. doi:10.1590/S0044-59672004000200004.
6. ^ a b c Berlo, Janet Catherine; Phillips, Ruth Bliss (1998). Native North American Art. Oxford University Press. p. 56. ISBN 978-0-19-284218-3.
7. ^ a b Weinstein & Dumas 2008, p. 203.
8. ^ Silverman & Isbell 2008, p. 307.
9. ^ Watters 1997, pp. 92–94.
10. ^ Milanich 1994, p. 86.
11. ^ Fontana, Bernard L.; Robinson, William J.; Cormack, Charles W.; Leavitt, Earnest E. (1962). Papago Indian Pottery. Seattle, Washington: University of Washington Press, on behalf of the American Ethnological Society. p. 57\. OCLC 869680.
12. ^ Silverman & Isbell 2008, p. 369.
13. ^ a b "Woodland Period - St. Johns Cultures - 500 BC to 1500 AD". Pelotes Island Nature Preserve. Archived from the original on 6 March 2015. Retrieved 14 April 2019.
14. ^ Wilson, C. Dean (2014). "Taos Black-on-White". New Mexico Office of Archaeological Studies. Retrieved 14 April 2019.

## References

[edit]

* Milanich, Jerald T. (1994). Archaeology of Precolumbian Florida. Gainesville: University Press of Florida. ISBN 0-8130-1273-2.
* Silverman, Helaine; Isbell, William (2008). Handbook of South American archaeology. New York: Springer. ISBN 978-0-387-75228-0.
* Watters, David R. (1997). "Maritime Trade in the Prehistoric Eastern Caribbean". In Samuel M. Wilson (ed.). The Indigenous People of the Caribbean. Gainesville: University Press of Florida. pp. 88–99. ISBN 0-8130-1531-6.
* Weinstein, Richard A.; Dumas, Ashley A. (2008). "The Spread of Shell-Tempered Ceramics along the Northern Coast of the Gulf of Mexico" (PDF). Southeastern Archaeology. 27 (2). Maney Publishing: 202–221. Archived from the original (PDF) on 25 April 2012. Retrieved 5 November 2011.

## External links

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* Common Inclusions and/or Tempers \- Images (including micrographs) of shards with various tempers.