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?



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

Some purples were possible. When you hear that purple dye was hard to get, it was that a specific kind of purple dye was hard to get, and it was that colour in particular that was associated with royalty. Other purples were limited by the available red and blue dyes, so weren’t able to produce something that looked like Tyrian Purple.

Blue was even harder to produce then purple. There are not many plants and minerals that have a lasting blue color. Of course its cost varied depending on region as some areas did have some sources of blue pigments. However if you had access to purple sea snails then it was much cheaper to make purple from that then to mix the very expensive blue dies with red dies.

As someone who paints a lot, I can tell you there’s purple and there’s “purple.” Mixing any red and blue will get you kind of a yucky hue of purple. The really nice, rich hues are hard to mix out of just straight red and blue.

So it’s already hard to do with ready-made paints, imagine doing it out of crushed mineral pigments. It would be super hard and likely not very high quality

>Couldn’t ascestors have just mixed red and blue, instead of laboriously extracting it from sea snails?

Yeah, but it looks like crap. It gets wet and the red runs more than the blue, and it comes out all splotchy, and your customer looks like a poor person pretending to be rich, which is worse than not looking rich at all. And even before that happens, the color is never quite right.

In ancient times they didn’t have access to nearly as many pigment sources as we do today. Mainly because they hadn’t been discovered and mined yet, but also due to limits in trade networks.

While some colors like Red and Black (Charcoal) and very easy to find because of the abundance of minerals and such of that color, other colors are very difficult to find.

Blue pigment was historically even more difficult to produce than purple. The only available vibrant sources of blue were very expensive liked crushed gemstone (Lapis Lazuli)

Speaking as as a painter you have to understand that mixing pigment doesn’t always give great results. Mixing Red and Blue for example often results in a purple with a greyish tinge instead of being vibrant. So it’s not as easy as it sounds.

The particular pigment you are likely referring to is the sea snail purple dye that is referred to in the Bible. It was highly sought after because of it’s vibrant color, but was so expensive that it was reserved for royalty.

But there were other ways to get purple dyes. The Chinese for example had Han purple which was one of the first synthetic dyes. Exactly how it was made though has been lost to time.

The blues they had access to were mostly bluish-greens. The reds they had access to were mostly reddish-oranges. When you mix those, you get sort of a baby-poop brown color instead of purple.

The *REALLY* deep reds, deep blues, and deep purples almost all came from the same snails, just fermented differently. (There’s one deep blue that came from the indigo plant, but it was almost as valuable as the snails).

Green is also hard to make. Arabic is a green mineral that makes a vibrant colors. It had a period where it was used in fancy wallpapers and dresses. Took them awhile to realize it made people fucking crazy and sick.

Another problem was a lot of pigments (especially anything with red in it) would fade very quickly with exposure to sun and/or water. Much worse than today. So it wasn’t just about finding the right hue. Finding stable (dye-fast) pigments was tricky on its own.

Blue was the hardest to get. Which is why it was reserved for Mary in Christian motifs. So no… also I’m sure you couldn’t mix those colours like we do with paints today.

I don’t mean to hijack this but I’ve found its very difficult to get opaque purple glass seed beads. I’ve been told they’re difficult to make. Is this at all for similar reasons?

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.