lac dye

Ingredients

lac, sticklac, borax, sodium carbonate, ashes

Preparation Steps

Original Recipe Text

Based on the Ibn Bādġs manuscript (c. 1025), the recipe 'red ruby from the lukk' (Chapter 6) involves grinding the resin (sticklac) and adding a basic solution. The mixture is filtered to remove impurities and residual resin. For this specific Koran formulation, the recipe adds borax and sodium carbonate derived from ashes to the water; notably, no alum is used as a complexing agent (p. 4).

Evidence

"Microspectrofluorimetry detected the presence of a lac dye chromophore in all the manuscripts studied and ascribed it to specific medieval recipes for three of the manuscripts. This was based on the very good matches obtained with our database of paint reconstructions... the dark reds found in the Koran compared very well with the recipe ‘to make red ruby from lukk’ from Ibn Bādġs text (11th c.)"

Remarks

The Koran manuscript (1198) contains only traces of its original illumination. Infrared spectroscopy (microFTIR) identified a proteinaceous binder combined with shellac resin, the latter confirmed by the presence of erythrolaccin (max at 474 nm) via microspectrofluorimetry (p. 5, 8).