By means of scanning electron microscopy combined with energy dispersive X-ray spectroscopy (SEM-EDS) and X-ray photoelectron spectroscopy (XPS), counterfeited Roman Republican coins are investigated to decipher some aspects of the manufacturing methods and to evaluate the technological ability of the Roman metallurgists to produce thin silver films. The results demonstrate that over 2000 ago important advances in the technology of thin film deposition on metal substrates were attained by Romans that produced counterfeited coins by combining sophisticated micro- and nano-plating methods and tailored surface chemical modification based on the mercury-silvering process. The ancient metallurgists were able systematically to manipulate metals at a micro and nano scale to produce adherent precious metal layers with a uniform thickness ranging from one to a few micrometers. Romans were able to create the appearance of solid silver coins without knowledge about the chemical-physical processes but using only their experienced skill [1]. Furthermore, the results suggest that, contrary to the more recent times, counterfeited coins were likely produced by the issuing official authorities too. The production was aimed firstly to save expensive metals as much as possible allowing profitable large-scale production at a lower cost. The driving forces could have been a lack of precious metals, an unexpected need to circulate coins for trade and/or a combinations of social, political and economic factors that requested a change in money supply. Finally, useful information on degradation agents have been achieved to tailor the selection of conservation methods able to save these important witnesses of art, technology and economy. [1] G.M. Ingo, G. Guida, E. Angelini, G. Di Carlo, A. Mezzi, G. Padeletti, Acc. Chem. Res. 46, 2365 (2013).
Roman sophisticated micro- and nano-technologies to manufacture counterfeited coins
GM Ingo;C Riccucci;F Faraldi;M Pascucci;G Di Carlo;G Fierro
2016
Abstract
By means of scanning electron microscopy combined with energy dispersive X-ray spectroscopy (SEM-EDS) and X-ray photoelectron spectroscopy (XPS), counterfeited Roman Republican coins are investigated to decipher some aspects of the manufacturing methods and to evaluate the technological ability of the Roman metallurgists to produce thin silver films. The results demonstrate that over 2000 ago important advances in the technology of thin film deposition on metal substrates were attained by Romans that produced counterfeited coins by combining sophisticated micro- and nano-plating methods and tailored surface chemical modification based on the mercury-silvering process. The ancient metallurgists were able systematically to manipulate metals at a micro and nano scale to produce adherent precious metal layers with a uniform thickness ranging from one to a few micrometers. Romans were able to create the appearance of solid silver coins without knowledge about the chemical-physical processes but using only their experienced skill [1]. Furthermore, the results suggest that, contrary to the more recent times, counterfeited coins were likely produced by the issuing official authorities too. The production was aimed firstly to save expensive metals as much as possible allowing profitable large-scale production at a lower cost. The driving forces could have been a lack of precious metals, an unexpected need to circulate coins for trade and/or a combinations of social, political and economic factors that requested a change in money supply. Finally, useful information on degradation agents have been achieved to tailor the selection of conservation methods able to save these important witnesses of art, technology and economy. [1] G.M. Ingo, G. Guida, E. Angelini, G. Di Carlo, A. Mezzi, G. Padeletti, Acc. Chem. Res. 46, 2365 (2013).I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
