A diffractive pigment blend or composition is provided which includes a plurality of groups of all-dielectric diffractive pigment flakes. The pigment flakes of each group each include one or more dielectric layers for providing a background color, at least one of which includes a diffractive structure for providing a diffractive effect. Each group of pigment flakes provides a different diffractive effect, and the diffractive pigment blend or composition provides a combined diffractive effect that is a combination of the different diffractive effects. The combined diffractive effect may be a neutral white diffractive effect or may include a reversal in color travel.