Abstract: A colored magnetically attractable toner powder containing magnetically attractable material and a coloring substance containing at least one thermoplastic resin and, as coloring constituent a mixture of fluorescent dyes, at least one dye being of the formula wherein X is an anion, such as, for example, tetrafluoroborate, boron fluoride, perchlorate, hexafluorozirconate or ethyl sulphate. The dye is preferably used in combination with a fluorescent dye of the type C.I. Basic Violet 1 1:1 (C.I. 45174) and possibly yellow-fluorescent dye. Improved magenta and red toner powders are obtained in this manner.