Abstract
A scarab found in grave 25 of the Monte Prama necropolis, near Cabras, Oristano, Sardinia, is of special importance for the archaeological interpretation and dating of this important archaeological site. The object has been misinterpreted in the past as composed by bone: recent archaeometric analyses showed that it is a glazed steatite of Egyptian origin and that the altered surface contains interesting phases crystallized during the high-temperature interaction of the Mg-rich talc core with the alkali-rich glass used for glazing. A novel single crystal X-ray diffraction analysis of one of the phases indicates that it is a new compound having the milarite-osumilite structure type, with a peculiar composition close to (Na1.52K0.12□0.36)(Mg3)(Mg1.72Cu0.16Fe0.12)(Si11.4Al0.6)O30, not reported for naturally occurring minerals. The structural and crystal chemical features of the compound, together with the known high-temperature stability of the series, allow a complete interpretation of the glazing process and conditions, based on direct application of the glaze on the steatite core with subsequent treatment at temperatures above 1000 °C.
Similar content being viewed by others
References
Mont’e Prama Prenda ‘e Zenia, Un programma di intervento della Soprintendenza per i Beni Archeologici delle Province di Sassari e Nuoro eseguito presso il Centro di Conservazione e Restauro di Sassari (CCA Centro di Conservazione Archeologica di Roma 2011). http://www.monteprama.it/. Accessed 20 March 2012
G. Lilliu, La civiltà nuragica. Sardegna Archeologica, Studi e Monumenti 2 (Carlo Delfino Editore, Roma, 1999)
G. Lilliu, La Civiltà dei Sardi. Dal Paleolitico all’età dei Nuraghi (Edizioni il Maestrale, Nuoro, 2003)
C. Tronchetti, Sard. Corsica Balear. Antiq. v. 2007, 99 (2008)
C. Tronchetti, in Il Mediterraneo di Herakles, ed. by P. Bernardini, R. Zucca (Carocci Editore, Roma, 2005), pp. 145–167
C. Tronchetti, in Studies in Sardinian Archaeology II: Sardinia in the Mediterranean, ed. by M.S. Balmuth (University of Michigan Press, Ann Arbor, 1986), pp. 41–59
A.F. Gorton, Egyptian and Egyptianizing Scarabs: A Typology of Steatite, Faience, and Paste Scarabs from Punic and Other Mediterranean Sites (Oxford University Committee for Archaeology, Oxford, 1996)
A. Stiglitz, Sard. Corsica Balear. Antiq. v. 2007, 87 (2008)
A. Stiglitz, Lo scaraboide della tomba 25, in La Pietra e Gli Eroi. Le Sculture Restaurate di Mont’e Prama, ed. by A. Usai (Direzione Generale per le Antichità, Roma, 2012)
I. Angelini, G. Artioli, Analisi archeometriche sullo scarabeo ed i vaghi di collana, in La Pietra e Gli Eroi. Le Sculture Restaurate di Mont’e Prama, ed. by A. Usai (Direzione Generale per le Antichità, Roma, 2012)
M. Nakahira, T. Kato, Clays Clay Miner. 12, 21 (1963)
M. Wesolowski, Thermochim. Acta 78, 395 (1984)
M. Zhang, Q. Hui, X.-J. Lou, S.A.T. Redfern, E.K.H. Salje, S.C. Tarantino, Am. Mineral. 91, 816 (2006)
M.S. Tite, M. Bimson, World Archaeol. 21, 87 (1989)
M.S. Tite, A.J. Shortland, A. Bouquillon, in Production Technology of Faience and Related Early Vitreous Materials, ed. by M.S. Tite, A.J. Shortland, Monography, vol. 72 (Oxford School of Archaeology, Oxford, 2008), pp. 23–36
G.M. Sheldrick, SHELX-97, Programs for Crystal Structure Analysis (University of Göttingen, Germany, 1997)
N. Nguyen, J. Choisnet, B. Raveau, J. Solid State Chem. 34, 1 (1980)
E.N. Maslen, A.G. Fox, M.A. O’Keefe, in International Tables for Crystallography, vol. C, Mathematical, Physical and Chemical Tables, Part 6, ed. by E. Prince (International Union of Crystallography, Chester, 2006), pp. 554–590
F.C. Hawthorne, M. Kimata, P. Cerny, N. Ball, G.P. Rossman, J.D. Grice, Am. Mineral. 76, 1836 (1991)
W. Winter, T. Armbruster, C. Lengauer, Eur. J. Mineral. 7, 277 (1995)
W. Winter, A. Berger, B. Muller, W. Pannhorst, J. Am. Ceram. Soc. 76, 1837 (1993)
K. Lambrinou, K. Vleugels, A.R. Boccaccini, J. Am. Ceram. Soc. 90, 590 (2007)
R.D. Shannon, Acta Crystallogr. A 32, 751 (1976)
K. Abraham, W. Gebert, O. Medenbach, W. Schreyer, G. Hentschel, Contrib. Mineral. Petrol. 82, 252 (1983)
Acknowledgements
The investigation was possible thanks to the collaboration with the Soprintendenza per I Beni Archeologici per le Province di Cagliari e Oristano in the person of Dr. Marco Edoardo Minoja and Dr. Alessandro Usai, who allowed access to the archeological material.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Artioli, G., Angelini, I. & Nestola, F. New milarite/osumilite-type phase formed during ancient glazing of an Egyptian scarab. Appl. Phys. A 110, 371–377 (2013). https://doi.org/10.1007/s00339-012-7125-x
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00339-012-7125-x