Yes, Easter eggers can lay eggs in ANY color including brown, white, blue, green, cream, etc. All eggs are white underneath(on the inside) with exception to *true* blue which is blue all the way through the shell. and all colors are dominant to white..
Easter Eggers is a general term that describes a bird that may not conform to any standard of perfection with regards to comb type, feather pattern, egg color, skin color, shank color, bearded or clean faced, etc. Some hatcheries sell them with incorrect "I" spelling Americana and usually state they are "meant to represent the breed but not for show". The term Easter Egger *generally*
implies that at least one of the parent was from blue egg genes.. Ameraucana, Araucana, Cream Legbar, EVEN other EE, etc.
Genetics being as complex as they are.. those that play into egg color are many factors (about 15 genes from what I recall reading).. most not relevant to comb type, despite being a once popular belief.
Very few hatcheries (or folks) have done testing to see if their birds are homozygous for blue..
First (colored) eggs.. may rarely be at their true shade of whatever they're going to be.
I personally would call an Ameraucana that didn't meet SOP as pet quality or cull rather than resorting to calling it an EE, but folks can do whatever pleases them.
This SOP chart for blue Ameraucana eggs has a wide range and variety of what is considered "accepted" shades of blue. (some are a little green and some are extra pale). image from google for educational purposes..
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