I am a bit color blind (some of the chart dots I do not see), but I see most colors (unless you ask my wife). When I hold the knife close to any light in the house, I see blue-green spots. They could be purple and I see blue green. The bar has some of the same blue-green tint to me. I see only brown in hand for the others. I agree most of the pieces have the blue green tint in the pics. A new set of shots with a different background are less blue to me. The top pic is with room light only (which is pretty dim at night). The other pics are with the new light. PS - Doug you can say I told you so here about the background color.
I have some later Formatum that I think is cool from Italia: Aes Formatum Oscan-Latin shell with Ribs obv-rev 4th BCE Aes Formatum Oscan-Latin shell 4th BCE