A Multianalytical Approach for the Study on Manufacturing Process in Ancient Bronze Coffin From Luristan, Western Iran

In this study, a recently discovered metallic coffin from the Chubtarash village, near Khorramabad, Luristan area, western Iran is investigated to identify alloy composition and manufacturing process. It is a large metallic bathtub-like coffin in which a skeleton is found with two gold strips covering its eyes and mouth. The coffin has four metallic handles that are joined to the bathtub body with pins. The coffin has been made in one piece but has been broken into some pieces during burial time. For this study, two samples from different parts of the coffin were selected. They have been analyzed with inductively coupled plasma-mass spectroscopy (ICP-MS), scanning electron microscopy coupled with energy dispersive X-ray spectroscopy (SEM-EDS), and metallography methods to identify alloy composition and manufacturing process. Results of chemical analysis showed that the coffin is made of binary copper-tin alloy. Other elements such as Zn, Pb, and As are detected as minor components. In fact, these elements cannot be considered as the alloying constituent in the composition. The microstructure of bronze in scanning electron microscopy-backscattered electron (SEM-BSE) micrographs shows that the thick edge of the coffin has a two-phase microstructure including alpha matrix and eutectoid mixture, while thin body includes a single phase alpha solid solution. Further, it is visible that the bronze in the coffin is corroded heavily at the thin body area. Etched microstructure of the coffin includes equi-axed grains with twin lines and strain bands indicating application of a cycle of cold working and annealing to shape this large bronze coffin into one piece.

[1]  R. Naseri,et al.  Technical Studies on the Bronze Age Metal Artefacts from the Graveyard of Deh Dumen, South‐Western Iran (Third Millennium BC) , 2016 .

[2]  Ata Hasanpour,et al.  Microscopic study on some Iron Age bronze objects from Western Iran , 2016, Heritage Science.

[3]  Omid Oudbashi,et al.  Iron Age tin bronze metallurgy at Marlik, Northern Iran: an analytical investigation , 2017, Archaeological and Anthropological Sciences.

[4]  Parviz Davami,et al.  Metallography and microstructure interpretation of some archaeological tin bronze vessels from Iran , 2014 .

[5]  Rui J. C. Silva,et al.  Arsenical copper and bronze in Middle Bronze Age burial sites of southern Portugal: the first bronzes in Southwestern Iberia , 2014 .

[6]  S. Srinivasan.  Megalithic and Continuing Peninsular High-Tin Binary Bronzes: Possible Roots in Harappan Binary Bronze Usage? , 2013, Transactions of the Indian Institute of Metals.

[7]  D. Caschera,et al.  Micro-chemical and micro-structural investigation of archaeological bronze weapons from the Ayanis fortress (lake Van, Eastern Anatolia, Turkey) , 2013 .

[8]  I. Kovács,et al.  Archaeometallurgical characterization of the earliest European metal helmets , 2013, Materials characterization.

[9]  C. Lundstrom,et al.  “Biblical” bronze coins: new insights into their timing and attribution using copper and lead isotopes , 2013, Archaeological and Anthropological Sciences.

[10]  V. Gouda,et al.  Characterization of Egyptian bronze archaeological artifacts , 2012 .

[11]  Rui J. C. Silva,et al.  Technological continuity in Early Iron Age bronze metallurgy at the South-Western Iberian Peninsula – a sight from Castro dos Ratinhos , 2010 .

[12]  Lesley D. Frame,et al.  Metallurgical investigations at Godin Tepe, Iran, Part I: the metal finds , 2010 .

[13]  Rui J. C. Silva,et al.  Microstructural Signatures of Bronze Archaeological Artifacts from the Southwestern Iberian Peninsula , 2010 .

[14]  E. Haerinck,et al.  Luristan exacavation documents VIII: early Bronze Age graveyards to the west of the Kabir Kuh (Pusht-i Kuh, Luristan) , 2010 .

[15]  C. Thornton.  The Emergence of Complex Metallurgy on the Iranian Plateau: Escaping the Levantine Paradigm , 2009 .

[16]  Rui J. C. Silva,et al.  Orientalizing Artifacts from Fraga dos Corvos Rock Shelter in North Portugal , 2009 .

[17]  S. J. Fleming,et al.  Bronze in Luristan : Preliminary analytical evidence from copper/bronze artifacts excavated by the belgian mission in Iran , 2005 .

[18]  G. Philip,et al.  Copper Metallurgy in the Jordan Valley from the Third to the First Millennia BC: Chemical, Metallographic and Lead Isotope Analyses of Artefacts from Pella , 2003 .

[19]  E. Pernicka,et al.  ENERGY DISPERSIVE X‐RAY FLUORESCENCE ANALYSIS OF ANCIENT COPPER ALLOYS: EMPIRICAL VALUES FOR PRECISION AND ACCURACY , 1996 .

[20]  N. Meeks.  TIN‐RICH SURFACES ON BRONZE–SOME EXPERIMENTAL AND ARCHAEOLOGICAL CONSIDERATIONS , 1986 .

[21]  V. Pigott,et al.  The Metals Trade in Southwest Asia in the Third Millennium B.C. , 1986, Iraq.