I am not sure that the term dichroic applies to this faceted Kuro-Oribe style surface but it definitely has two rather distinct appearances and a few others depending on the light source creating a different vision of the work. In this first picture utilizing only natural sunlight the green is quite easy to see showing off the wonderful clay texture underneath with areas of flowing blue, black and white all cascading down the surface complete with dramatic built up areas of glaze at high points further accentuating the varying effects. In the second photo this bowl takes on an entirely different demeanor and presence where the tungsten light source has turned the green into a rich deep amber with areas of almost black with swirled blue-white residing within.
I should also mention that there is actually a third appearance which is quite interesting, if the bowl is resting on a particular shelf just before sundown, the surface starts out as a visible green but as the sun sets and the incandescent lighting takes over the bowl slowly shifts from green to the amber tone. With my limited skills I have tried photographing this effect to zero success, the camera either reads it as all green and shadow or amber and shadow but to the eye it is both. So my conclusion is this is a dichroic effect where the different light wave lengths are interfered with by the surface of the glaze and/or dispersed differently causing two distinct yet related appearances, one showing off the copper and the other making full use of the iron. I am reasonably sure this is what is happening but if somebody that has an indepth knowledge of this principle feels otherwise, please let me know.
"Vision is the art of seeing what is invisible to others." Jonathan Swift