It occurred to me that it would be nice to be able to dye cloth orange. So, looking in “Colours from nature” by Jenny Dean, I found a number of methods.
Here is the first one, on the left is a red made as normal with no mordant piece of wool, and on the right of it the same stuff, no mordant, but heated for a while in a madder solution with vinegar added to it:
You can see that the result is very red for the original madder, showing it can dye without a mordant, albeit it is a darker red because I heated it strongly. Making the solution more acidic made it kind of orange, but unevenly and it looks rather odd.
Two other uses of madder were tried. One was unheated, no vinegar solution, no mordant, left to soak for some days. The other was the left over solution of madder and vinegar. The first one on the left was in the solution for half an hour to an hour with some agitation now and then. The second was left in overnight for at least 12 hours, both being from the left over solution.
The third one on the right was from the unheated solution, and spent 2 days in it, no vinegar used.
The result is that the unheated soak for a few days gave a very light, not very good orange, not acceptable really. The best result was from the slightly warm older solution of madder and vinegar, the colour is deep, and what we think of as orange. The long soak was just too long and the colour isn’t right.
Thus the best madder one was a long soak in the cool acidised solution. If I’ve remember the order I did things in properly….
It seems that using brazilwood with an acidic modifier gives an orange as well. Again, using vinegar as the modifier, I put some brazilwood into a beaker and heated it with the same wool as before. The result was somewhat poor. I heated and nearly simmered the brazilwood for nearly 45 mins as it said, then put hastily alum mordanted wool into it, and boiled it for another 45 mins, left it to soak for 2 or 3 hours, and the result was the fabric on the far right of this photo:
Pretty bad really, it was a lot easier to get a red with the brazilwood than orange.
Of course the slight problem is that I am not really sure what the medieval method of getting orange was. Just to add to the difficulty, the word “Orange” was quite new to the language, appearing in the late 15th/ early 16th centuries, and what the Tudor Tailor people sell as something approximating orange is called tawny:
(Ref. For orange is page 159 of “The senses in late medieval England” by C. M. Woolgar)
Said book by Woolgar also says that tawny was a mottled cloth of orange, brown and yellow colour, which I assume means it was dyed in the skein, i.e. the threads that were to be woven were dyed, not the finished cloth.
So I feel happy enough dyeing cloth this colour, although perhaps only for late medieval use onwards.
What I have had trouble finding is actual period recipes online. I am not aware of many books on medieval dyeing that look at the topic as a whole, rather there are scholarly papers on specific aspects, and many books on using plants to dye with, and not so much that links them together. If anyone knows of any I would be grateful, otherwise will be reduced to badgering dyers I know to write such a book.
Here’s one colleciton of links:
unfortunately many are broken.
There is also this scholarly set of links, which looks interesting:
Oh yeas, a quick note on the chemistry. The Alizarine molecule (see here: http://homepages.gac.edu/~jimholte/documents/JCE1981p0301.pdf) which is the main constituent of the redness changes colour depending on the pH of the solution, or so wikipedia says. Once again though I find the major problem is that according to the internet, the only source for this information is a paywalled paper from 40 years ago, and nobody else at all knows what actually happens with it all. Or rather, they all repeat the same information picked up from somewhere years ago, which is no use at all to me. The closest I can find to useful information is from 19th century scientific papers, which are all paywalled. Naturally not being part of a university is a handicap.
Naturally they didn’t know about the chemistry back then (I must try and see if there were any medieval theories of how dyeing worked) but they would have experimented with different additives and mordants and used what worked for them. Some towns had good water for dyeing, and became famous in part because of that. Others had hard water with lots of calcium and that tends to make dyeing poor.