Histology, cytology and other related scientific disciplines study the microscopic anatomy of tissues and cells. In order to demonstrate good tissue and cellular structure, the samples need to be stained in a correct manner. Bismarck Brown Y powder dye is used in various staining methods in microscopy. It is a metachromatic dye used in histology for staining tissues, acid mucins, cartilage, and bones. It is also used in cytology. It is most commonly used as a counterstain to Gentian Violet.