Iron hematoxylins use iron salts as a mordant and are typically used in special stains. This is because they can demonstrate more tissue structures than alum hematoxylins, such as myelin and elastic fibers. One of the best known Iron hematoxylins is Weigert's Hematoxylin, which is used in the Verhoff-Van Gieson stain for elastic fibers as shown in the image.
