What is "persian blue"

Persian blue (not to be confused with Prussian blue) comes in three major tones: Persian blue proper—a bright medium blue; medium Persian blue (a medium slightly grayish blue that is slightly indigoish); and a kind of dark blue that is much closer to the web color indigo; this darker shade of Persian blue is referred to as Persian indigo, dark Persian blue, or regimental.

Other colors associated with Persia include Persian pink, Persian rose, Persian red and Persian green.