Why was purple pigment history difficult to produce? Couldn’t ascestors have just mixed red and blue, instead of laboriously extracting it from sea snails?
In: Chemistry
Up front, I dye fabrics, mostly wool, with plant materials as a hobby. I have read up on and tried variety of processes, mordants, modifiers and materials, ranging from madder root to avocado pits to lowly onion skins .
The blue from woad and indigo is hard to extract, as it requires a more involved process than just soaking plant parts in cold or hot water and waiting. Modern chemical treatments can speed up the process, but preparing an indigo vat is still a pain in the butt.
The hallmarks of Tyrian Purple, the color made from snails, was its richness and colorfastness (resistance to fading).
Any peasant could stain their clothes purple with mashed beets, red grapes, berries etc, but it would fade to a faint pink after a matter of days to months, even with a strong mordant like alum or tannin from oak galls. Over-dyeing indigo on madder (the most common color-fast red dye in Antiquity) ends up with a color that is much too dark. Madder root treated with ammonia gives a nice purplish red, but its no Tyrian Purple. Punctelia lichen can give a vivid purple color, but its a time-intensive process, upwards of ten weeks. I’ve tried it twice and ended up with bupkis, probably due to my inexperience.
Latest Answers