The present invention provides ink-jet inks, systems, and methods for marking documents as original. Specifically, an aqueous ink-jet ink can comprise an ink vehicle; and a sufficient amount of particulates having directionally dependent light reflective properties within the ink vehicle such that when the ink-jet ink is substantially dried on a desired substrate, a multi-colored reflected light is emittable in the presence of a light source. Printing documents as original can be carried out for compensation, as a service, or by providing cartridges containing these inks to clients and/or customers.