Editing Haematoxylin (section)

==Use as a writing and drawing ink==
Haematoxylin has been used as the primary component of writing and drawing [[inks]], although the timing of first use as an ink is unclear.<ref name="Centeno 2009" /> Haematoxylin was also added to some [[iron gall ink]]s, which take time to fully darken when applied to paper.<ref name="Barrow, 1948" /><ref name="Centeno 2009" /> In this case the Haematoxylin provided some initial colour before the iron gall reached its full depth of colour.<ref name="Barrow, 1948" /><ref name="Centeno 2009" /> [[William Lewis (scientist)|William Lewis]] in 1763 is credited with being the first to use haematoxylin as an additive in iron gall inks.<ref name="Neevel, 2003" /> In 1848, [[Friedlieb Ferdinand Runge]] produced a heamatoxylin ink that was non-acidic, using a potassium chromate as the mordant, which had the advantage of not corroding steel pens.<ref name="Neevel, 2003" /> [[Van Gogh]] is known to have used haematoxylin ink with a chrome mordant in a number of his drawings and letters.<ref name="Neevel, 2003" /><ref name="Centeno 2016" /><ref name="Centeno 2009" />