The biggest difference I can find: Sapphire Gems are supposed to lay brown eggs, Sapphire Skys are supposed to lay olive eggs (with a few laying brown anyway, but that's not the color they are really trying for.)
Grace (Light Brahma) and Ruth (Silver Laced Wyandotte) look like they are the right breed.
I have trouble with many of the blue breeds and hybrids, so I'm not really sure about Idgie and Agnes.
I think Agnes might be developing a small crest on the head, but it's hard to be sure at this age...