Gill's Hematoxylin is a specially formulated solution for use as a biological stain for the nuclei and nuclear chromatin of normal and abnormal cells whether in whole or sliced cells. Our Gill's Hematoxylin is designed to use at its full strength. It is microfiltered prior to shipment; therefore, filtration before use is not required. For repeated use further filtration is recommended. At the discretion of the user, the Gill's Hematoxylin No. 2 and No. 3 may be diluted with ethylene glycol (25% is recommended) to produce a weaker stain solution.