The progress of logwood extract

Hematoxylin, C₁₆H₁₄O₆, from the extract of logwood, crystallizes as a trihydrate with the water molecules inside helical channels. It was the first organic compound used to deliberately stain a salt crystal and as such played a central role in the general development of the subject of dyeing crystals. We discuss this development and, moreover, show that efforts to stain (NH₄)H₂PO₄ crystals with hematoxylin in 1879 provided evidence of enantioselective crystal chemistry recognizable with the unaided eye. What motivated nineteenth century chemists to dye crystals? Why and how was hematoxylin selected as the first colorant, and what were the consequences of this selection? In order to answer these questions, we offer an integrated history of hematoxylin. We trace logwood extract from the height of the Mayan civilization, through the development of the baconian scientific method, during the Atlantic slave trade, and in supramolecular stereochemical associations while dyeing crystals. Along this journey we endeavour to reflect upon the science and conscience of a stereochemist.