One of the vendors at the farmer's market sells different colored egg. The shells have shades of green from deep, light, and olive, some are pink-ish, light peach, mottled brown, and of course brown. These eggs have smaller whites than regular eggs and therefore have less protein and their yolks are dark yellow to almost orange. I was told that these eggs are from Ameraucana chickens.
Last week I boiled a few and forgot to time them. I usually cook eggs by letting the water come to a boil, turn the heat off, cover the pan, and leave the eggs for 10 minutes, then I rinse them immediately in very cold water. One of the things I can't stand is boiled eggs with green rings around the yolks. There is no difference in taste but it just looks unappetizing. When I removed the shells I could see the green through the whites. I noticed that the green ring is thicker than normal and I was not repulsed by it because it looks interesting with the contrast of colors, green against yellow and almost orange in the middle making the sliced eggs look like kabocha squash. After a day in the refrigerator the thick green rings disappeared on the remaining few slices of eggs. I wonder if this is true for all eggs, that is, the green ring disappearing after a few days, hmm.