I have been doing more natural dyeing with Louise Spong of South Downs Yarn, (see link on the right of the home page), this time focusing on greens. The photo below shows a range of green shades from one of our dyeing sessions.

Although green is the most common colour in nature,  producing green from natural dyes is not as straightforward as one might expect. Mossy greens can usually be achieved by using an iron modifier on yellow-dyed yarn and using a copper modifier on fibres dyed with plants such as weld often gives lime green. However, a true grass green is almost impossible to obtain from a single dye and has to  be achieved by dyeing blue over yellow or vice-versa.

The photo below of colours from weld shows from left to right: weld + iron modifier, weld with no modifier, weld + copper modifier.

There are numerous sources of yellow but indigo is the only reliable source of true blue. I tend to prefer to dye yellow first and then use the blue dye; I feel this gives greater control over the final colour because the indigo blue can be added gradually by dipping the fibres in the vat several times. If the vat is weak and each dip is brief, the green colour can be built up gradually until you reach the desired shade and depth. Some dyers prefer to start with blue fibres and then over-dye them with the yellow dye and this also gives good results. The shade of yellow determines the shade of green. Dyeing blue over a bright clear yellow gives grass green; mustard yellows tend to produce mossy greens, whilst over-dyeing pale yellow or a beige yellow often gives a turquoise green. It is also important to remember that most yellow dyes require a mordant, in which case the yarn you use will need to be mordanted even though indigo does not need a mordant. Yellow dyes that do not require a mordant include rhubarb root and saffron. However, saffron may be considered too expensive to use in the dye pot, although about 5% should be enough to achieve a reasonable yellow..

The photo above shows the development of turquoise green from pale yellow over-dyed in indigo.   Later in the year I shall be writing an article on dyeing greens for the “Journal for Weavers, Spinners & Dyers” and this will give more information and include several photographs.

 

Last year I dislocated my hip for the third time and sadly had to cancel the workshop “Colours of the Romans” at Fishbourne Roman Palace. This was particularly frustrating, as I had had to postpone a previous workshop at Fishbourne a couple of years ago when I dislocated my hip the first time. Fortunately, this earlier workshop was re-scheduled but my physical health has become so  unreliable that I have decided to “retire” from workshops, except for those on a one-to-one basis at my home.

 

As I had already done all the preparations for “Colours of the Romans”, including printing off all the information sheets and sample cards and preparing the wool sample sets, I decided to offer the workshop to the education department at Fishbourne, rather than let all my work go to waste. Katrina Burton, Head of Learning at Fishbourne, and Beverly Lee, the Education Officer, took up my offer and earlier this year they came to my home for the workshop. Louise Spong, from South Downs Yarn, also joined us and assisted with the heavier physical work, which has become too much for me following my recent hip surgery.

 

The dyes used by the Romans included madder, kermes, weld, woad, walnut hulls, oak galls, saffron and lichen purple. With the exception of kermes, which is no longer available, these were the dyes we used on the course.

 

According to Pliny the Elder, orange, red and purple were colours worn by priests and priestesses. Purple was the colour for high officials and the purple clothing of Emperors was dyed purple using a dye from shellfish of the Murex species. The dye colour was known as Tyrian or Imperial Purple and vast quantities of shellfish were required to produce relatively small amounts of dye material. This mollusc dye was overused and the supply of shellfish gradually dwindled. By the Middle Ages, the Tyrian Purple dye industry had become considerably reduced and with the fall of Constantinople in 1453 it more or less disappeared. A purple dye from the lichen Roccella tinctoria was used by the Romans to simulate the purple from shellfish.

 

MADDER (Rubia tinctorum)

Madder is a source of red dye and, according to Pliny, it was cultivated near Rome c.50AD. It is interesting to note that, although there is evidence that the Romans used madder when they were in Britain, its use in Britain appears to have ceased for a period after the Romans left (c.410AD). This would seem to suggest that the Romans imported madder from Rome as a prepared dried dyestuff, rather than cultivating it in Britain.

KERMES (Kermes vermilio)

This red insect dye comes from the shield louse Kermes vermilio, which lives on the kermes oak found in various parts of the Mediterranean. Today kermes is very difficult to obtain, although the insects may still occasionally be found on host trees around the Mediterranean.

WELD (Reseda luteola)

Weld is one of the most ancient dyes and has better colour-fastness than most other yellow dyes. The yellow from weld was the colour worn by the six Vestal Virgins and was also the colour of Roman wedding garments.

WOAD (Isatis tinctoria)

Woad was used by the Romans as a source of indigo blue dye. Indigo from Indigofera tinctoria was also used by the Romans, but as a paint pigment rather than as a textile dye. It was probably brought to Rome from India in small quantities via the land route.

LICHEN PURPLE (Roccella tinctoria / Ochrolechia tartarea)

This dye is sometimes referred to as orchil. Relatively few species of lichens will give purples and as lichens are protected they should never be harvested indiscriminately from the wild. For the workshop, we used the lichen Ochrolechia tartarea, as Roccella tinctoria is not found in northern Europe. For experimental purposes, make sure you have identified the lichen accurately and use only a very small quantity, for example a piece about the size of a 50p coin. To make lichen purple solution, put the lichen into a strong glass jar and add 2 parts water and 1 part household ammonia. Put the lid on firmly and leave the solution for several weeks, shaking or stirring it two or three times each day. The solution will become a deep purple colour and is then ready to use. (Note: stale urine contains ammonia and can be used instead of household ammonia) When the solution is ready to use, strain it carefully into a dye pot, add more water and add the fibres to be dyed. Simmer them gently for 45 minutes, turn off the heat and then leave them to steep overnight. Then rinse well. Lichen purple is not a very fast dye and materials dyed with lichen purple should be stored in a dark place away from daylight. (NB Ammonia gives off unpleasant fumes and should be used with caution.)

OAK GALLS (Quercus spp.)                                                             

Oak galls are rich in tannin and were used by the Romans in combination with iron to make a black dye. When used alone as a dye, oak galls give tan and light brown colours.

WALNUT HULLS (Juglans spp.)

According to Pliny, the outer green hulls of walnuts were used as a brown dye for wool and hair.

SAFFRON (Crocus sativus)

According to Pliny, saffron was cultivated in Abruzzo and Sicily & was used as a yellow dye. Although saffron is very expensive, only a very small amount is required for dyeing and for the workshop samples we used only about half a gramme.

 

Another dye reportedly used for yellow was turmeric, from the roots of Curcuma longa, which was imported from the Orient during Imperial times.

 

Alum

The Romans used alum as a mordant and also iron but, as with madder, it is likely that alum was imported from Italy for Roman use and was not available in Britain after the departure of the Romans until it was imported in the later Anglo-Saxon period.

 

The photo below shows the colours we achieved on the samples we dyed at the workshop.

 

 

 

Top row left to right: weld, weld overdyed with madder (orange shade), madder, madder overdyed with woad, lichen purple & walnut hulls

Middle row left to right: saffron, saffron overdyed with woad (greens), more saffron, walnut hulls overdyed with woad, walnut hulls overdyed with weak lichen purple, walnut hulls overdyed with madder, walnut hulls, weld overdyed with woad (green)

Lower row left to right: oak galls, oak galls plus iron (grey), oak galls overdyed with woad, woad, lichen purple overdyed with woad, lichen purple & lichen purple plus clear vinegar (reds)

 

More information on most of these dyes can be found in my latest book “A Heritage of Colour”.