Spending the day with Angora Rabbit texts, I have decided to try and combine everything I have read about this "color amount" of rabbit genetics into usable format.
From what I can gather, rabbits are born with 4 units of BLACK pigment, and 3 units of YELLOW. These pigments will be allowed expression as per the "c" genes they inherit alongside.
C allows all color to be fully expressed. The bunny will have a black pupil and brown eyes. Fur will be as dark as it can be.
chd will allow all BLACK but only 1 YELLOW, and bunny will have a black pupil and mottled blue gray or gray eyes. Fur will be as dark as it can be.
chm will allow 3 BLACK but NO YELLOW, and bunny will have a reddish glowing pupil and light brown eyes. Fur will be a TAD lighter than it can be.
chl will allow 2 BLACK but NO YELLOW, and bunny will have (strangely enough) a reddish glowing pupil and brown eyes. Fur will definitely be lighter all over and "shaded" on the body.
ch will allow only 2 units of BLACK to be expressed, and these stay on the POINTS of the rabbit (ears, feet, tail), and bunny will have a red pupil and red eyes. These points will be darker when the air is cold! Fur will be void of color or white.
c allows NO color to be expressed anywhere, and bunny will have a red pupil and red eyes and white fur.
Right now in my barns I have all colors of the above eyes. Neat. I have been stymied by chd/chm/chl. It is confusing, for they work together and can tweak the color expression to the point that you have NO IDEA what is doing what. I don't do enough breeding in quick succession to clearly see all possibilities, so I rely on seeing adult rabbits elsewhere and the color names that are given to them.
This is not always enough help, for many breeders have no idea how it all works and giving color names is just a good guess half the time!