LAUSR

Abstract Nishapur is a historical city in the ancient Khorasan region, located in the northeast of Iran. Due to its location on the Silk Road, Nishapur enjoyed great economic prosperity and as a result contains many archaeological sites from prehistoric to post-Islamic periods. Shahrak-e Firouzeh is one such site, dating back to 2nd millennium BC, containing numerous metallic objects and metallurgic remains from silver refining by cupellation. This study investigates the manufacture of a unique silver lidded dish decorated with bas-relief mythological designs. Different techniques, including SEM-EDS, micro-PIXE, and Metallography were used to characterise the dish. Results obtained by micro-PIXE and SEM-EDS reveal the use of an intentional silver alloy containing about 92 wt.% silver and about 3.80 wt.% copper. Date also suggested the use of an advanced silver extraction process to obtain high purity silver. The presence of elements such as calcium were associated with exposure to the burial environment and the extraction process. Metallographic examination revealed that this extremely thin object was decorated with complex bas-relief designs which had been produced by cold working, and annealing based upon the presence of twin straight lines on some parts of the surface and the changing gradation in tiny grains and twin uneven lines on the raised parts.