AMP 05 July 2021

A D V A N C E D M A T E R I A L S & P R O C E S S E S | J U L Y / A U G U S T 2 0 2 1 2 7 to long-term segregation of lead, originally retained in solid solution after cupellation and working and annealing. ~AM&P Note: The authors recently prepared an article for a new (2022) edition of ASM Handbook, Volume 12, Fractography, which discusses the types of damage in ancient metals, including tin bronze and high-silver artifacts[17]. The implications of all these types of damage for conservation and restoration are discussed in the article. Formore information: OmidOudbashi, associate professor, department of conservation of cultural and historical properties and archaeometry, Art University of Isfahan, P.O. Box 1744, Isfahan, Iran, o.oudbashi@aui.ac.ir, www. aui.ac.ir. Russell Wanhill, emeritus principal research scientist, aerospace vehicles division, Royal Netherlands AerospaceCentre,AmsterdamandMark- nesse, the Netherlands, rjhwanhill@ gmail.com References 1. B.W. Roberts, C.P. Thornton, and V.C. Pigott, Development of Metallurgy in Eurasia, Antiquity, 83, p 1012-1022, 2009. 2. M. Radivojević, et al., Tainted Ores and the Rise of Tin Bronzes in Eurasia, c. 6500 Years Ago, Antiquity, 87, p 10301045, 2013. 3. J. Bayley, D. Dungworth, and S. Paynter, Archaeometallurgy, Centre for Archaeology Guidelines, English Heritage, National Monuments Record Centre, Great Western Village, Kemble Drive, Swindon, UK, 2001. 4. R.F. Tylecote, A History of Metal- lurgy, Second Edition, Maney Publishing, London, UK, 2002. 5. J.P. Northover, Properties and Use of Arsenic-copper Alloys, Old World Archaeometallurgy, Deutsches Bergbau Museum, Bochum, Germany, p 111-118, 1989. 6. W.L. Kent, The Brittle Ranges of Bronze, Journal of the Institute of Metals, 35, p 45-53, 1926. 7. G. Dardeniz, Why Did the Use of Antimony-bearing Alloys in Bronze Age Anatolia fall Dormant After the Early Bronze Age? A Case from Resuloğlu (Çorum, Turkey), PLoS One, 15(7): e0234563, 34 pages, 2020, https://doi. org/10.1371/journal.pone.0234563. 8. T. Rehren, L. Boscher, and E. Pernicka, Large Scale Smelting of Speiss and Arsenical Copper at Early Bronze Age Arisman, Iran, Journal of Archaeological Science, 39(6), p 17171727, 2012. 9. C.P. Thornton, The Emergence of Complex Metallurgy on the Iranian Plateau: Escaping the Levantine Paradigm, Journal of World Prehistory, 22(3), p 301-327, 2009. 10. H.N. Lechtman, Arsenic Bronze: Dirty Copper or Chosen Alloy? A View from the Americas, Journal of Field Archaeology, 23(4), p 477-514, 1996. 11. S. Hansen and B. Helwing, Die Anfänge der Silbermetallurgie in Eura-sien, Von Baden bis Troia: Ressourcennutzung, Metallurgie und Wissenstransfer, Verlag Marie Leidorf GmbH, Rahden, Germany, p 41-58, 2016. 12. P. Craddock, Production of Silver Across the Ancient World, ISIJ (Iron and Steel Institute of Japan) Journal, 54(5), p 1085-1092, 2014, https://doi. org/10.2355/isijinternational.54.1085. 13. C.E. Conophagos, Le Laurion Antique et la Technique Grecque de la Production del’ Argent, Ekdotike Hellados, Athens, Greece, 1980. 14. N.H. Gale and Z.A. Stos-Gale, Ancient Egyptian Silver, Journal of Egyptian Archaeology, 67, p 103-115, 1981. 15. R.J.H. Wanhill, T. Hattenberg, and J.P. Northover, EBSD of Corrosion, Deformation and Precipitation in the Gundestrup Cauldron, Ligas Metálicas, Investigação e Conservação, University of Porto, Portugal, p 47-61, 2008. 16. R.J.H. Wanhill, Stress Corrosion Cracking in Ancient Silver, Studies in Conservation, 58(1), p 41-49, 2013. 17. R.J.H. Wanhill and O. Oudbashi, Fractography of Ancient Metallic Arti- facts: Archaeometallurgical Fracture Analysis and Restoration and Conservation Aspects, ASM Handbook, Volume 12, Fractography, to be published in 2022. (a) (b) Fig. 6 — Electron back-scatter diffraction metallographs of corrosion damage in a sample from the Gundestrup Cauldron[15]. (a) Inverse pole figure color-coded map, showing equiaxed grains and annealing twins. (b) Boundary rotation angle map showing retained cold-work as dislocations (red) and deformation twins (narrowly spaced irregular yellow boundaries). The corrosion is preferentially associated with retained cold work and has been identified as stress corrosion cracking (SCC)[16]. GET ENGAGED, GET INVOLVED, GET CONNECTED Join the conversation about historic metals. The archaeometallurgy community on ASM Connect welcomes new participants. Visit connect.asminternational.org, search for the Archaeometallurgy Committee, and get into the conversation!

RkJQdWJsaXNoZXIy MTYyMzk3NQ==