Disclosed is a toner for developing an electrostatic image, a full color toner kit comprising the toner and an image formation method employing the a full color toner kit, the toner comprising at least a resin and a colorant, wherein the colorant includes C.I. Pigment Blue 60 having a powder X-ray diffraction peak (2.theta.) at 6.3.+-.0.2.degree. and 13.0.+-.0.2.degree..