Jeremy, I surely agree. If you saw the Eagle chip you would call it almost black. You can hardly see the design at all unless you tip it to the light. I am interested in the design more than the color, especially on such a chip saw dark. More care would be taken on chips that have the color variant as the prime difference. I think there are other plaques like your 500 franc piece without the black stripe through the middle. Thing is, unless you shoot them all together under the same conditions, it's hard to tell which color is correct.
I have a off white chip of a similar eagle design. This one is an engraved style with out ink with the eagle flopped. Again the scan is weak and the photo with care on lighting is much better.