There is currently no book available on this species or the other 2 for that matter.. Forums are you best bet at present..Your 1st question is one that has been asked many times..The popular vote gets co dom..Theres another type called the granite which is very similar in looks but it gets the recessive vote..? I've played with and produced this species for about 10 years and I've got questions too..It seems only time and produce will provide what we're thirsting for..IMO, they are the same and co dom but the hets may not always display its look..??
Wish I could do better but at present theres no FACT that I'm aware of..It is an EXTREMELY variable species for fact..New looks pop up each year..A super marble/granite would have to be marbles/granites that have been line or inbred.. Keep in mind there is NOT a more variable species..