Rock or Maran ?

[Stacyoung13]

Probably Cuckoo Marans, but I'll leave you to judge, as I'm not sure I can see enough of your birds to tell for certain. Here's how you can tell:

PBRs have yellow skin. CMs have white. (Leg or shank colour is not skin colour. To see the colour of their skin, look at the bottom of their feet.) Yours appear to have white skin/beaks, but the picture doesn't really show a lot of skin.

Cuckoo is the same colour pattern as Barred, but Cuckoo is messier because the bird has fast-growing feathers, which make for uneven striping. Barred chickens should be slow-feathering. Yours look cuckoo.

Most CMs in the US will have lightly feathered legs, conforming to the French standard. Again, your birds aren't showing a lot of leg in the picture.

Here are pics of their feet and legs. Hope they help.
camera on my phone sucks. I hope you can see what you need to see. I thought that they looked white to me.

 

[sylviethecochin]

Definitely Cuckoo Marans.

 

[oregonkat]

My Cuckoo Marans does not lay a particularly dark brown egg, more medium brown and very uniform. My Black Copper Marans hens lay a much darker egg. I think the Black Coppers lay the darkest (most of the time, I have a BCM that lays a pale brown with spots ) eggs of all the Marans!