Hostname: page-component-7bb8b95d7b-lvwk9 Total loading time: 0 Render date: 2024-09-22T13:38:48.250Z Has data issue: false hasContentIssue false

Towards an appreciation of Minoan metallurgical techniques: information provided by copper alloy tools from the Ashmolean Museum, Oxford1

Published online by Cambridge University Press:  27 September 2013

P. Northover
Affiliation:
Department of Materials, Oxford
D. Evely
Affiliation:
Oxford

Abstract

A group of ten copper and copper alloy Minoan tools from the Ashmolean Museum's Cretan collection is analysed. Though the component elements are recorded, the emphasis is on metallographic aspects of the objects. By considering these sets of information together we can learn how craftsmen treated the types of metal available in order to suit the requirements of the intended products. Many details of the stages undergone by the metal in its transformation into a finished item can be recovered. Much of this process is dictated by the physical properties of the metal itself. Two standards of finishing existed, relating to the available metal and its intended use. Though limited in the range of its conclusions, the study shows that the return of information, especially in an area of investigation left unexplored, well recompenses the loss of the snippet required for analysis.

Type
Articles
Copyright
Copyright © The Council, British School at Athens 1995

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

2 Egypt:Lucas, A. and Harris, J. R., Ancient Egyptian Materials and Industries (4th edn; London, 1962).Google ScholarMesopotamia:Moorey, P. R. S., Materials and Manufacture in Ancient Mesopotamia, The Evidence of Archaeology and Art: Metals and Metalwork, Glazed Materials and Glass (Oxford, 1985).Google Scholar

3 Charles, J. A., ‘The first Sheffield plate’, Antiquity, 42 (1968), 278–85.CrossRefGoogle Scholar

4 Betancourt, P. P.et al., ‘Metallurgy at Gournia’, MASCA Journal, 1.1 (1978), 78.Google Scholar

5 Weinstein-Balthazar, J., Copper and Bronze Working in Early through Middle Bronze Age Cyprus (SIMA Pocketbook 84; Jonsered, 1990).Google Scholar

6 Miron, E., Axes and Adzes from Canaan (PBF 9; Stuttgart, 1993).Google Scholar

7 Some terms will need explanation: with the chisels, the cutting edge will expand out from the shaft in a ‘flare’, and may itself be ‘straight’ or curved. With the double-axes, the ‘wedging-grooves’ are a pair of grooves, one each side of the shaft-hole and on the main axis: they are assumed to have held cross-pins that were driven into the handle. ‘Rsh’ and ‘Osh’ denote a round and oval shaft-hole respectively. Catling, H. W., Cypriot Bronzework in the Mycenaean World (Oxford, 1964)Google Scholar; Boardman, J., The Cretan Collection in Oxford: The Dictaean Cave and Iron Age Crete (Oxford, 1961)Google Scholar; Pope, M., ‘Cretan axe-heads with Linear A inscriptions’, BSA 51 (1956), 132–5Google Scholar; Evely, D., Minoan Crafts: Tools and Techniques, i (SIMA 92. 1; Göteborg, 1993).Google Scholar

8 See generally Craddock, P. T., ‘The composition of the copper alloys used by the Greek, Etruscan and Roman civilizations, 1: the Greeks before the archaic periodJournal of Archaeological Science, 3.2 (1976), 93113.CrossRefGoogle Scholar

9 For more on these tool types: catalogue and discussion on development, manufacture and use, see Evely (n. 6).

10 Boardman (n. 6), 52, 225. But see Craddock (n. 7), 100 (his item 302), who is prepared to include it.

11 See further and in more detail such books as Cottrell, A., An Introduction to Metallurgy (2nd edn; London, 1975).Google Scholar Also, for illustration of some of the terms, Lüthy, H. and Pressl-Wenger, R., ‘Métallographie de quelques objets en bronze d'Auvernier’, in Rychner, V. (ed.), Auvernier 1968–1975: le mobilier métallique du bronze final. Formes et techniques (Cahiers d'archéologie romande, 37: Auvernier, 6; Lausanne, 1987), 183–98, at 185.Google Scholar

12 In an ideal bronze, frozen in equilibrium conditions, the maximum solid solubility is 15% tin, which shows how far from ideal normal solidification is.

13 As a rule of thumb, the full effects of annealing can be achieved by heating up the metal to some 30% (if pure) or 50% (if an alloy) of the appropriate melting point.

14 Hardness testing is measured in Vickers units (HV). The process consists of impressing the sample with a diamond tip of known size and under known pressure (the variables within the system are appended to the HV: thus HV1, HV2.5, and so on), and measuring the size of the resultant indentation. The resistance put up by the hardness of the metal sample will affect the size of the indentation, and a value is obtained by reading off this against a table.

15 Buchwald, V. F. and Leisner, P., ‘A metallurgical study of twelve prehistoric bronze objects from DenmarkJournal of Danish Archaeology, 9 (1990), 64102.Google Scholar

16 Hughes, M. J., Northover, J. P., and Staniaszek, B. E. P., ‘Problems in the analysis of leaded bronze alloys in ancient artifacts’, OJA 1.3 (1982), 359–64.Google Scholar

17 Northover, J. P., ‘Non-ferrous metallurgy in British archaeology’, in Henderson, J. (ed.), Scientific Analysis in Archaeology (OUCA Monographs, 19; Oxford, 1989), 213–36.Google Scholar

18 See Craddock (n. 7).

19 Stansby, A. W., The Production Sequence of a Bronze Age Axe (unpublished thesis for Part II BA degree in Metallurgy and Science of Materials, Dept of Materials, Univ. of Oxford, 1984)Google Scholar; Buchwald and Leisner (n. 14).

20 Rychner, V., ‘La matière première des bronziers lacustres’, Archéologie suisse, 7 (1984), 73–8Google Scholar; J. P. Northover (unpublished).

21 Stansby (n. 18).

22 For SAM see Junghans, S., Sangmeister, E., and Schröder, M., Kupfer und Bronze in der frühen Metallzeit Europas: die Materialgruppen beim Stand von 12.000 Analysen (Studien zu den Anfängen der Metallurgie; Berlin, 19681974).Google Scholar For the lead isotope work, the researches of N. H. Gale and Z. A. Støs-Gale have produced a deal of relevant information.