Maybe actual "natural" lighting would help as well - meaning sunlight.
No manufactured bulb/LED will always give the real look of natural sunlight. And sunlight changes the variableness of similar shades throughout the day as well.
It get's complicated as to why the lights are allowed to be sold as "natural," but the CRI index has to be 100 for correct color. A "temperature" rating of 5000K will be about what sunlight is a little after 12 noon (depending on your global location - told you it get's complicated!)
I have been photographing a lot of glass insulators, where color accuracy is crucial, since the 90s and written several articles about it to guide others. I have found the ONLY way to get accurate color in all cases is actual sunlight.
And then there is the problem with the actual elements the camera's sensor is made of absorbing different color wavelengths and changing thee colors...but never mind!
So although I have not tried it with coins, I suspect sunlight will solve the problem. Let us know!
How much squash could a Sasquatch squash if a Sasquatch would squash squash?
Download and read: Grading the graders
ineptitude and No FG Kennedy halveshttps://ln5.sync.com/dl/7ca91bdd0/w...i3b-rbj9fir2