I was told they are Blue Maran x Wheatan Maran and could hatch out all four colors.
These were "bonus" eggs in a purchase I made of another breed so I only got 4 Maran eggs. All I know is that of the three that developed, two hatched. One was Wheaten, one "black" and the other died during hatch but it was a beautiful slate blue.
Forgive my cluelessness...

