Mauve comes from the combination of the Chocolate gene (Choc+) and the Blue gene (Bl).

Breeding a chocolate male over a splash female will result in 100% mauve chicks. 

Breeding a Chocolate Male over a Blue hen will result in sex-linked chicks, all males will be BLACK OR BLUE (split for chocolate) and all females will be BLACK or MAUVE ( CHOC + BLUE). 

Below I have added chart showing what your result would be if you breed any combination of BBS or CHOC male over all 6 combinations of hens. This will show you how Mauve interacts.