I have only had buckeyes, gold sex-link & Black australorps -- the individual species lay different colors - If I found your eggs in my nests - I'd say the dark one was a GSL and the lighter one from a BA. The BA's (mine anyway) have a little mauve, or almost purplish tint to them. The buckeyes lay much lighter color eggs than the GSL's, but no purple in them.
Question for more experienced folks -- one of my Buckeyes lays 'wrinkled' eggs. They are a little smaller than the other buckeye - other than that they are fine. I'm not breeding these guys, they're just for eggs, else she'd need to be culled for genetics. Read somewhere that wrinkled eggs were a sign of a virus - but this has been going on since she first started laying a couple of months ago - Am thinking it's more just her style, so to speak, and as long as I'm not furthering the trait - who cares. Of course, she's my fav chook - took me awhile to figure out which chick was laying the wrinkled egg & was disappointed to see who it was...
Question is - does this ALWAYS mean virus -- don't see that it's catching - or been passed on to the others - just checking to see if anyone else has seen this.
Otherwise - all chicks seem in great health, active, get almost an egg a day a chick in this their first winter.