In mixing group B2 we find Royal Blue(8) which, when mixed with equal part of Blue Sky from the B1 mixing group, becomes Primary Blue. We can borrow and mix in a little Blue Sky or Baby Blue from B1 mixing group, to get our other B1 Blues into a more Primary Blue color vibe.
Royal Blue is a rich, distinguished, deep and extremely versatile Blue. It works especially well to mix with colors headed towards Red and can easily be lightened or darkened to give a solid cool Primary Blue mood. It works great for creating shadows by using a complimentary color from RY2 group like Tang or Dark Orange.