I Thought This Was Unusual For A Coin.

https://en.numista.com/catalogue/pieces2106.html

This is a standard coin.
The field of white with yellow / gold devices was unexpected.
Never saw that before when photographing coins.

It is a photo.
Which is why I posted such an unexpected result.
This may be proof:
I tilt the coin in the light and see how differently the color reflects.
I've never lied or jerked anyone around here on this forum.
I later thought maybe I should post in the photography forum.

Inverse cameo- I didn't think of it that way.
So yes you are right.
And I see it during some sessions.
Coin placement, lighting angles, diffiusers and reflectivity can produce a "flip-flop" of field resulting in either black or white.
A coin on white paper can be white background, or it may flip to a black background even though no black paper is used.
Just a phenomena of my equipment and how it is all manipulated.

Looks like someone was doing axial lighting on a brilliant/cameo proof with very flat fields, and then adjusted the image brightness to blow out the entire field. Not a great photo technique but for sure gives a very interesting result.