What causes failure (overheating) during lithic heat treatment?

Original Paper

Abstract

Heat treatment of lithic raw material, i.e. the intentional alteration of silica rocks for improving their knapping quality, is a process that may require great care and precisely controlled conditions in order to avoid failure due to overheating. The physical causes of overheating remain poorly understood leading to problems in the interpretation of heat-treated artefacts and/or fire-related taphonomic alteration of different types of silica rocks. This driving force of overheating is investigated by a set of experimental heat treatment sequences with different ramp rates and different volumes of flint with a well-defined mineralogical composition, porosity and water content. The results of this experiment show the main cause of heat-induced fracturing to be the vapour pressure in fluid inclusions within the rocks. Heterogeneous thermal expansion could be discarded. The interdependence between volume and heating rate is also shown. These results have implications for the study of archaeological heat-treated rocks, the understanding of taphonomic heat-induced fracturing of silica rocks and experimental flint knapping.

Keywords

Heat treatment Thermal alteration Overheating Flint Flint knapping Lithic raw material 

References

  1. Anderson DC (1978) Aboriginal use of Tongue River silica in northwest Iowa. Plains Anthropol 23(80):149–157Google Scholar
  2. Anderson DC (1979) Prehistoric selection for intentional thermal alteration: tests of a model employing southeastern archaeological materials. Midcont J Archaeol 4(2):221–254Google Scholar
  3. Ahler SA (1983) Heat Treatment of Knife River Flint. Lithic Technology 12:1–8Google Scholar
  4. Binder D (1984) Systèmes de débitage laminaire par pression: exemples chasséens provençaux. In: Tixier J, Inizan ML, Roche H (eds) Préhistoire de la pierre taillée, 2: économie du débitage laminaire: technologie et expérimentation: IIIe table ronde de technologie lithique. Meudin-Bellevue, octobre 1982. Cercle de Recherches et d’Etudes Préhistoriques, Paris, pp 71–84Google Scholar
  5. Bordes F (1969) Traitement thermique du silex au Solutréen. Bull Soc préhistorique fr 66(7):197CrossRefGoogle Scholar
  6. Brown KS, Marean CW, Herries AIR, Jacobs Z, Tribolo C, Braun D, Roberts DL, Meyer MC, Bernatchez J (2009) Fire as an engineering tool of early modern humans. Science 325(5942):859–862CrossRefGoogle Scholar
  7. Burnham C, Holloway J, Davis N (1969) Thermodynamic properties of water to 1,000°C and 10,000 bars. Geological Society of America, BoulderGoogle Scholar
  8. Crabtree DE, Butler BR (1964) Notes on experiment in flint knapping: 1 heat treatment of silica materials. Tebiwa 7:1–6Google Scholar
  9. Domanski M, Webb JA, Boland J (1994) Mechanical properties of stone artefact materials and the effect of heat treatment. Archaeometry 36(2):177–208CrossRefGoogle Scholar
  10. Eriksen BV Colourful Lithics – the “Chaîne Opératoire” of heat treated chert artefacts in the early mesolithic of Southwest Germany. In: Kind CJ (ed) After the ice age. Settlements, subsistence and social development in the Mesolithic of Central Europe, Materialhefte zur Archäologie in Baden-Württemberg, 2006. Stuttgart: Konrad Theiss Verlag, pp 147–153Google Scholar
  11. Flörke OW, Köhler-Herbertz B, Langer K, Tönges I (1982) Water in microcrystalline quartz of volcanic origin: Agates. Contrib Mineral Petrol 80(4):324–333CrossRefGoogle Scholar
  12. Graetsch H, Flörke OW, Miehe G (1985) The nature of water in chalcedony and opal-C from Brazilian Agate Geodes. Phys Chem Miner 12(5):300–306CrossRefGoogle Scholar
  13. Graetsch HA, Grüberg JM (2012) Microstructure of flint and other chert raw materials. Archaeometry 54(1):18–36. doi:10.1111/j.1475-4754.2011.00610.x CrossRefGoogle Scholar
  14. Griffiths DR, Bergman CA, Clayton CJ, Ohnuma K, Robins GV (1987) Experimental investigation of the heat treatment of flint. In: Sieveking GdG, Newcomer MH (eds) The human uses of flint and chert. Proceedings of the fourth international flint symposium held at Brighton Polytechnic 10–15 April 1983. Cambridge University Press, Cambridge, pp 43–52Google Scholar
  15. Hanckel M (1985) Hot rocks: heat treatment at Burrill Lake and Currarong, New South Wales. Archaeology in Oceania 20:98–103Google Scholar
  16. Inizan ML, Roche H, Tixier J (1976) Avantages d’un traitement thermique pour la taille des roches siliceuses. Quaternaria Rom 19:1–18Google Scholar
  17. Inizan ML, Tixier J (2001) L’émergence des arts du feu: le traitement thermique des roches siliceuses. Paléorient 26(2):23–36Google Scholar
  18. Léa V (2005) Raw, pre-heated or ready to use: discovering specialist supply systems for flint industries in mid-Neolithic (Chassey culture) communities in southern France. Antiquity 79:1–15Google Scholar
  19. Mandeville MD (1973) A consideration of the thermal pretreatment of chert. Plains Anthropol 18:177–202Google Scholar
  20. McLaren AC, Cook RF, Hyde ST, Tobin RC (1983) The mechanisms of the formation and growth of water bubbles and associated dislocation loops in synthetic quartz. Phys Chem Miner 9(2):79–94. doi:10.1007/bf00308151 CrossRefGoogle Scholar
  21. Mercieca A (2000) An experimental study of heat fracturing in silcrete. Aust Archaeol 51:40–47Google Scholar
  22. Mercieca A, Hiscock P (2008) Experimental insights into alternative strategies of lithic heat treatment. J Archaeol Sci 35(9):2634–2639CrossRefGoogle Scholar
  23. Micheelsen H (1966) The structure of dark flint from Stevns, Denmark. Medd Dansk Geol Foren 16:285–368Google Scholar
  24. Mourre V, Villa P, Henshilwood CS (2010) Early use of pressure flaking on lithic artifacts at Blombos Cave, South Africa. Science 330(6004):659–662CrossRefGoogle Scholar
  25. Olausson DS, Larsson L (1982) Testing for the presence of thermal pretreatment of flint in the Mesolithic and Neolithic of Sweden. J. Archaeol. Sci. 9(3):275–285Google Scholar
  26. Patterson LW (1995) Thermal damage of chert. Lithic Technol 20(1):72–80Google Scholar
  27. Price TD, Chappell S, Ives DJ (1982) Thermal alteration in mesolithic assemblages. Proc Prehist Soc 48:467–485Google Scholar
  28. Purdy BA (1974) Investigations concerning the thermal alteration of silica minerals: an archaeological approach. Tebiwa 17:37–66Google Scholar
  29. Rick JW, Chappell S (1983) Thermal alteration of silica materials in technological and functional perspective. Lithic Technology 12:69–80Google Scholar
  30. Roqué-Rosell J, Torchy L, Roucau C, Lea V, Colomban P, Regert M, Binder D, Pelegrin J, Sciau P Influence of Heat Treatment on the Physical Transformations of Flint Used by Neolithic Societies in the Western Mediterranean. In: International conference, Materials Research Society, November 2010, Boston, 2010. pp mrsf10-1319-ww1309-1302Google Scholar
  31. Schindler DL, Hatch JW, Hay CA, Bradt RC (1982) Aboriginal thermal alteration of a Central Pennsylvania Jasper: analytical and behavioral implications. Am Antiq 47(3):526–544CrossRefGoogle Scholar
  32. Schmidt P (2013) Le traitement thermique des matières premières lithiques: Que se passe-t-il lors de la chauffe ? Archaeopress, BAR International Series 2470, OxfordGoogle Scholar
  33. Schmidt P, Badou A, Fröhlich F (2011) Detailed FT near-infrared study of the behaviour of water and hydroxyl in sedimentary length-fast chalcedony, SiO2, upon heat treatment. Spectrochim Acta A Mol Biomol Spectrosc 81(1):552–559CrossRefGoogle Scholar
  34. Schmidt P, Masse S, Laurent G, Slodczyk A, Le Bourhis E, Perrenoud C, Livage J, Fröhlich F (2012) Crystallographic and structural transformations of sedimentary chalcedony in flint upon heat treatment. J. Archaeol. Sci. 39(1):135–144Google Scholar
  35. Schmidt P, Porraz G, Slodczyk A, Bellot-gurlet L, Archer W, Miller CE (2013) Heat treatment in the South African Middle Stone Age: temperature induced transformations of silcrete and their technological implications. J. Archaeol. Sci. 40(9):3519–3531Google Scholar
  36. Tiffagom M (1998) Témoignages d’un traitement thermique des feuilles de laurier dans le Solutréen supérieur de la grotte du Parpalló (Gandia, Espagne). Paléo 10:147–161CrossRefGoogle Scholar
  37. Wilke PJ, Flenniken J, Ozbun TL (1991) Clovis technology at the Anzick Site, Montana. J Calif G Basin Anthropol 13(2):242–272Google Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2013

Authors and Affiliations

  1. 1.Department of Prehistory and Quaternary EcologyEberhard Karls University of TübingenTübingenGermany
  2. 2.Muséum national d’histoire naturelle, Department de Préhistoire UMR 7194Centre de Spectroscopie InfrarougeParis Cedex 05France

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