Well, it's certainly not what I expected to find, but today I found these TWO beauties lying on the ground. (One was partially hidden) I'm assuming that they're both from my female turkey. No chicken I have could lay an egg that big. The only other possibility would be a Rouen duck (which I believe would be slightly tinted)
The big one weighs 68g & the smaller one weighs 62g
This is Pearl, who I believe is the egg layer! She "submits" to me every time I walk anywhere near her.