Black Copper Marans lay the darkest eggs in the business. Welsummers lay a medium dark egg in comparison. I no longer have my Wellie, she got eaten by a bear but her egg was a medium milk chocolate brown. Here is a pic of one of my egg cartons: The blue eggs one of top of the other bottom right are CCL eggs, the eggs immediately adjacent are Isbar green eggs: The darkest brown egg in there is a BCM egg but not the darkest they can get by any means, and the brown egg at the top left is a Cuckoo Marans egg.
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