Medal from Olomouc celebrating handover of the rule to Franz Joseph I in 1848. Contribution to the recent state of the gold proof issue

Filip Hradil, Vít Procházka, Lukáš Richtera
2017 Numismatické listy  
Unattractive stains on gold coins – sometimes wrongly described or mistakenly understood as gold corrosion – remained in focus of increased interest of scholars especially because of development of modern analytical techniques in the last decades. It is impossible to answer the primary questions about character and reasons of appearance of these stains without deep interdisciplinary knowledge. There is also another important question dealing with prevention of these stains and possibility of
more » ... d possibility of their gentle removal. The presented study tries to discover what caused appearance of the dark stains on the surface of the gold medal from Olomouc celebrating handover of the rule to Franz Joseph I and what is their chemical substance, and if it could be – in this case – a result and external effect of violation of the declared fineness.
doi:10.1515/nl-2017-0016 fatcat:ytauu6kkfzab3pqtzzp6xe5zj4