1. The Colour Index system of nomenclature is used for the naming of synthetic organic pigments. Pigments are given a Colour index name (e.g. Pigment Yellow 1 or PY1) and five or six digit number upon registration. www.Colour-Index.com (accessed 07.11.17).
2. The term “industrial scale” is apt because the chemical industry started as the dyestuff business in the 19th century where the cycle of discovery-monopoly-chemical modification drove the increase in chemical knowledge, dye innovation and industrial commerce.
3. Color of Art Pigment Database, http://www.artiscreation.com/Color_index_names.html (accessed 07.11.17).
4. A history of the international dyestuff industry;Morris;Am. Dyestuff Rep.,1992
5. The use of Raman microscopy and laser desorption ionization mass spectrometry in the examination of synthetic organic pigments in modern works of art;Lomax;J. Raman Spectrosc.,2014