Quoted from Whitenoise3000:As with old paintings, the colors fade and change over time. I wonder if the green people have is actually a fading from the original color.
I dont believe this is the case here as CPR has stated they had a NOS one to go off of. Also, do a Google search on this game and you will see that there appears to be two different versions of this glass. Just looked at IPDB and there is pictures that show the blue and green versions.