Which hematoxylin is most frequently used as a progressive stain?

• A. Mayer Hematoxylin
• B. Harris Hematoxylin
• C. Ehrlich Hematoxylin
• D. Gill Hematoxylin

Answer: (A)

Progressive staining relies on a hematoxylin that develops the nuclear color during the staining step without a separate differentiation step. Mayer's hematoxylin is the most frequently used for this approach because its aqueous formulation gives crisp, uniform nuclear staining that deepens with time and blueing, with good stability and reproducibility. This makes it reliable across many tissue types and reduces background staining. Other hematoxylins are more often used in regressive protocols or require careful differentiation to control staining, so they’re not the default choice for progressive staining.