[A new high definition histologic coloration method based on formic nigrosin].

Nigrosin, an aqueous blue-black acid dye of the azine series, in conjunction with Biebrich scarlet, orange G and formic acid as mordant, it is found an excellent triple panchromatic rapid stain for histological purposes. The staining so obtained permits a more brighter and well differentiated picture if the latter is observed by means of a microscope connected with a monitor, tuning colour strength adjustment.