Lithium carbonate is quite commonly used as an alkalising agent in histological techniques. A saturated or half saturated aqueous solution blues alum hematoxylin effectively. It is also incorporated into congo red and sirius red methods for amyloid. This is based on the observation that in an alkaline medium inonisation of amino groups is suppressed and, since both congo red and sirius red are acid dyes, including lithium carbonate in the staining solution inhibits any ionic reaction between the dyes and proteins. This allows the weaker dipole staining to occur.
One of the oldest and most traditional ways of demonstrating myelin is with lithium hematoxylin. These methods incorporate lithium carbonate into the staining solution with ripened hematoxylin.