I often see desriptions of late 3rd century Antoniniani as having a “silver wash”. I have always had a fanciful vision of a mint employee with a paint brush and pot of molten silver! Regardless, this has always seemed to imply the silver was added after the underlying base metal planchet was struck to ensure the finished product looked “silvery”. However that seems overly time consuming, even for such a labor intensive minting process that cranked massive quantities in those years. Any insights on how this process was implemented?
I have a page that talks about this http://www.constantinethegreatcoins.com/metallurgy/ and here is a page that links to the article by Vlachou, C., J. G. McDonnell, and R. C. Janaway. “Experimental Investigation of Silvering in Late Roman Coinage.” http://www.constantinethegreatcoins.com/articles/
