negative shadow

A recent post on the e-Sylum by Dick Johnson gives a name, negative shadow, to a kind of toning seen on struck silver coins where the devices and inscriptions a projected in toning onto the field.

This effect reminds me greatly of an effect on Roman coins discussed on Moneta-L back in 2004.



(The Roman coin image is from Warren Esty's page).

The most detailed explanation on Moneta-L came from a post by Robert Kokotailo of Calgary coin. I wonder if this is the same effect?

I'm glad to have a name for it! (If it is the same phenomenon.) The name most popular on Moneta-L was 'ghosting', which is also a technical term in numismatics for clashed die errors that leave a 'ghost' of the type on one side upon the other.