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How do you get corrosion off old coins? 

Corrosion
Polarization (electrochemistry)
Copper
Persian
Alloy

Answers from top 10 papers

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Papers (10)Insight
Open access•Journal Article•DOI
Technical studies on the mechanisms of corrosion and state of conservation of two hoards of Persian copper coins (folus) from the Safavid period in Iran
Elaheh Hajjari, Omid Oudbashi, Esmail Hemati Azandaryani 
04 May 2021-Journal of The Institute of Conservation
The presence of chloride compounds in the corrosion products showed that the coins have been suffering from ‘bronze disease’ so that any preventive conservation must include keeping the relative humidity of their storage and exhibition environments below 45%.
Journal Article•DOI
Analysis of corrosion layers in ancient Roman silver coins with high resolution surface spectroscopic techniques
Christopher J. Keturakis, Ben Notis, Alex Blenheim, A. C. Miller, Rob Pafchek, Michael R. Notis, Israel E. Wachs 
15 Jul 2016-Applied Surface Science
15 Citations
Determination of the microchemistry of surface corrosion layers on ancient silver alloy coins is important both in terms of understanding the nature of archaeological environmental conditions to which these ancient coins were exposed and also to help in their conservation.
Journal Article•DOI
Characterization of corrosion products on archaeological iron coins
Guo Lv, Zi Se Wang, Li Mei Wu, Chunchun Xu 
11 Jan 2011-Anti-corrosion Methods and Materials
3 Citations
The possible corrosion mechanisms for the iron coins were discussed based on the corrosion products. Originality/value – This study revealed the characterization of corrosion products on archaeological iron coins and may provide guidance ...
Journal Article•DOI
Corrosion current between fresh and old amalgam
G. Ravnholt, R.I. Holland 
01 Oct 1988-Dental Materials
12 Citations
The results indicate that galvanic corrosion occurs when fresh amalgam restorations are placed in contact with old ones, and that various amalgam combinations may give rise to considerably different corrosion rates.
Open access•Journal Article•DOI
Corrosion Performance of Cu-Based Coins in Artificial Sweat
J. Porcayo-Calderon, R. A. Rodriguez-Diaz, E. Porcayo-Palafox, Lorenzo Martínez-Gómez 
24 Nov 2016-Journal of Chemistry
6 Citations
Equivalent circuits confirmed that the corrosion performance of the Ni-Zn-Cu coins depends on the Zn/Ni ratio, such that decreasing this value decreases the corrosion resistance of the alloy.
Journal Article•DOI
Neutron tomographic analysis: Material characterization of silver and electrum coins from the 6th and 5th centuries BCE
Filomena Salvemini, Scott Olsen, Vladimir Luzin, Ulf Garbe, Joel Davis, T. Knowles, Kenneth Sheedy 
01 Aug 2016-Materials Characterization
16 Citations
Moreover, the state of conservation, corrosion processes and attempts to repair the coins can be determined.
Journal Article•DOI
An Electrochemical Simulation and Treatment Study for the Carbonate and Chloride Based Corrosion of Heritage Silver–Copper Alloys
Ahmad N. Abu-Baker, Ian D. MacLeod 
19 May 2021-Studies in Conservation
3 Citations
The potentiostatic methods showed excellent effectiveness in determining treatment parameters and monitoring the reduction process of the corrosion products on the coins, which helped to preserve surface details in the cleaning process and to prevent over-treatment.
Journal Article•DOI
Characterisation of corrosion layers formed under burial environment of copper-based Greek and Roman coins from Pompeii
Lucilla Pronti, Anna Candida Felici, M. Alesiani, Ombretta Tarquini, Maria Paola Bracciale, Maria Laura Santarelli, Giacomo Pardini, Mario Piacentini 
09 Aug 2015-Applied Physics A
15 Citations
Coins from the same stratigraphic unit have shown different morphologies of corrosion, probably due to different micro-environmental conditions.
Open access•Journal Article•DOI
Corrosion Performance of Cu-Based Coins in Artificial Sweat
J. Porcayo-Calderon, R. A. Rodriguez-Diaz, E. Porcayo-Palafox, Lorenzo Martínez-Gómez 
24 Nov 2016-Journal of Chemistry
6 Citations
Regardless of the chemical composition of the Cu-based coins, they showed similar polarization curves; particularly, the observed similarity in the anodic zone suggests that the corrosion mechanism is the same in all cases.
Journal Article•DOI
Further metallurgical analyses on silver coins of Trajan (AD 98–117)
M. Rodrigues, M. Rodrigues, Federica Cappa, Federica Cappa, Manfred Schreiner, Manfred Schreiner, Paolo Ferloni, Paolo Ferloni, Martin Radtke, Uwe Reinholz, Bernhard Woytek, Michael Alram, Michael Alram 
01 May 2011-Journal of Analytical Atomic Spectrometry
16 Citations
100 to 200 μm in the near surface regions of most of the coins could be observed, which is due to corrosion effects.

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