The Quest for Light-Fast Purple, Part One

Purple! This color has spelled trouble for the natural dyer for centuries, millennia even…

Tyrian purple, the famous purple used in antiquity, came from Phoenicia (around present-day Lebanon) where the coastal waters were full of snails of the Murex family, from which the dye (6,6′-dibromoindigo) was extracted.

In ancient times, Tyrian purple was an immense luxury, so expensive that only the very few could afford it. I don’t know exactly how expensive it was back then, but I looked up today’s price here: 27.444 kr per gram (that’s $4120 or 3675 euros). Per gram. I don’t know how much fabric that would have dyed, I’m guessing it couldn’t possibly be more than a kg (and probably much less) so we are talking about one expensive color.

I imagine there must have been quite the excitement when logwood purple hit the stage. Logwood (Haematoxylum campechianum) is a tree that grows in Mexico and Central America, and was brought back to Europe, where it became a much used dyestuff.

The dye molecule in logwood is hematoxylin, a molecule that is used for staining in cell biology even today!

Logwood can be used to dye a very nice purple on alum mordanted wool:


A very lovely purple indeed. But there’s just one big problem – the light-fastness is really low!

At a higher dyestuff to wool ratio, logwood and alum together give a blue color, which also has a terrible light-fastness.

My Danish book, “Farvning med planter” by Esther Nielsen, says that logwood blue was nevertheless used, and may have been OK for a while because people had little light indoors in the past. But the same book tells you that French dyers of high color were not allowed to have logwood in their workshops at all, because they also had alum, and those two together could be used to produce the inferior logwood blue which was forbidden for the dyers of high color – they had to dye blue with indigo.

Plain dyers, on the other hand, were allowed to have logwood, but they mainly used it to dye black. This is done by addition of iron, which makes the color somewhat more light-fast. The German name for plain dyer is “Schwarzfärber” which actually means dyer of black (this interesting article has more information on the dyer’s guild’s division into plain dyers and dyers of high color).

Historically, natural purple pretty much came to an end in 1856 with Perkin’s discovery of mauveine, the first synthetic dye. This discovery is often described as serendipitous, but I think that’s not so accurate. It is true that Perkins first made the molecule by happy accident, but he then noticed that the solution in his flask was purple. That was the first step. The second step was to quit his studies and turn mauveine into a successful business, something that required a lot of skill and effort over many years (this BBC program tells the interesting story, and also talks about the other top seller his company made: chemically synthesized madder red!).

But I’m not giving up on purple just yet, so I’ve decided to do a slightly systematic study of indigo overdyeing of some reds and pinks. To get an idea, I’ve played a bit with a color blending tool. Just to get an idea: this is a strong pink (cochineal) overdyed with weak blue (indigo), and  this is a weak red-orange (madder) overdyed with strong blue (indigo). Next step is to actually carry out the overdying experiment, more on those results later!


Trip to Japan – Kyoto, Part One

It’s been a bit quiet here at the blog over the last few weeks, and that’s because we’ve been in Japan on holiday. There are so many impressions to process, but here I’ll just share the ones that have to do with yarn and dyeing. Natural dyeing seems to be quite popular in Japan!

The first stop on our route was a very nice shop/workshop called Tezomeya. They have a full range of cotton clothing, which I really liked. Here’s a quick snapshot of their shop, taken with our small pocket camera so not the best, but just to give an idea:


Unfortunately, Japanese clothing sizes are not really made for me, a Dane of just above average height (actually, I tried on a pair of men’s trousers in another shop, and they were about 8 cm too short! The man in the shop commented that my legs were “too long”).

But my mother (who wears a much smaller size than I do) bought two excellent stylish t-shirts in organic cotton, one in a dark indigo, the other dyed with pomegranate.

The dyer (whose name I didn’t catch) was very friendly and showed me what he was up to that day – dyeing with a type of shellfish purple that is used in Japan. This is not the shellfish purple that was used in antiquity, but comes from a form of sea snail that people eat in Japan (raw or like escargots). It contains an inedible part, I’m supposing it’s some kind of gland, and this is the very part that contains a pink/purple dye. Seeing that I was interested in it, they gave me the shell of one of these creatures. Here it is:

shellback shellfront

A rather handsome seashell, I think, and quite large – about 12 cm long. Googling a bit about, it seems to me that this could possibly be a dye called akanishi, coming from Papuna venosa. This book about an excavation of an archeological site dating from around year 0, shows a picture of a shell, which to my eye looks a lot like the one I have, and says that “this shell is very common in the sea near [northern Kyushu] while we have found many crushed shells during excavations, which imply the use for purple dye”. Not impossibly far from Kyoto where we were, and 2000 years later, the species could still be a common one – so the story could fit together. But if someone knows more about this, I’d love to hear from you!

In Kyoto, we also went to the very yummy yarn shop Avril. Among other (non-natural dyed) things, I bought a skein of natural colored quite untreated lace weight silk. Here it is, posing along with an “antique” yarn spool from a Takayama “antique”/tourist trap shop. Another spool is still wrapped in its newspaper


I don’t know yet what I’ll make with this silk, but it seems to somehow beg to be combined with something indigo blue…