The 'black' ball you are referring to is indeed the Super form of the Cinnamon Pastel morph. Just to make sure you understand, Cinnamon Pastel is a morph that does not actually have any Pastel in it. I usually just call them Cinnamons myself to avoid the confusion there. Anyway, if you breed a Cinnamon to a Cinnamon then theoretically each egg has a 25% chance of being a normal, a 50% chance of being a cinnamon, and a 25% chance of being a super cinnamon. As you have already pointed out, however, I do not think it is possible to tell whether the super you produce will be solid brown or solid black. My guess would be that a black pastel (which is essentially the name for another mutation that looks a lot like the Cinnamon and functions like the cinnamon in terms of breeding for most morphs) would make a darker (and therefore closer to black) super. Hope this helps, and I hope I got all my info right.