It is common today to re-patinate ancient coins, using a variety of methods. Some are reversible, some not. They all have the same goal: to enhance the esthetic appeal of the coin by evening out unwanted colour differences and often also to give a smoother surface. Sometimes substances are applied to enhance the relief and mimic natural patination.
Every dealer and collector will have a personal view on this, ranging from full acceptance to full rejection. That is the way it should be. But when an artificial patina is applied specifically to hide poor preservation, we – imho - approach the area of criminal behavior.
Imagine that a poorly preserved coin is sold for USD 1,500. The buyer then applies a thick artificial patina to hide the corroded surface and made to mimic sandy patina (aka Syrian patina). Imagine that the artificial patina is made of sandy patina scraped off from genuine coins and then made into a glue which is painted on the corroded coin. Imagine that the price is now raised from USD 1,500 to USD 5,900.
Do collectors still want the coin with the fake patina if they know what the coin really looks like?
The coin posted here is now for sale. The upper photos are from the Heritage auction 21-22 Jan this year. The lower photos show the same coin as it is being offered now by a well-known seller. The seller does state “earthen patina applied”, which is true. The quality is given as “Choice VF” which is in any case very subjective.
My paper on the SPES PVBLIC coins was published early this year*, before this particular example surfaced, so it is not in the catalogue. I would have added a paragraph on it, warning potential buyers from acquiring it.
These are just my views, other may think differently.
* a 20-page extract (of 160 pages) is available on academia.edu:
https://independent.academia.edu/LarsRamskold
