Results from walnut hulls

Recently I conducted some experiments with fresh, dried and frozen walnut hulls, to see if there was any difference in the colour achieved from each. Using fresh green walnuts kindly donated by Deborah Barker and all collected at the same time from the same tree, some were put in the freezer immediately, some left to dry out and some used fresh from the tree. I used whole walnuts as this was easier than trying to separate the outer shell from the nut. The frozen and dried walnuts became dark brown and the fresh walnuts also appeared dark brown when I put them in the dye bath.

Fresh green walnuts

I put 2 walnuts in each of 3 containers, added samples of wool, silk and linen (no mordant) to each container and then added hot water. I decided to experiment with dyeing without further heat, so I put a lid on each of the containers and left them for about 4 weeks. I checked from time to time and stirred gently.

The results were interesting. There was little difference between the shades from each dye bath, although the results from the dye bath made with fresh walnuts seemed a little paler. I had expected the fresh walnuts to give the deepest shades and the dried walnuts the palest but strangely enough the results were the reverse, with the dried walnuts appearing to give slightly deeper shades. In all cases the colours were deeper than I usually get from dried walnuts. I assume that the fresh walnuts may not have given deeper shades because they were no longer fresh and green when the dye bath was made.

In my experience, the best way to get deep browns if using dried walnuts is to add clear vinegar to the dye bath to pH4.5. This I learned from Helen Melvin and I have found it particularly effective on wool and silk.

Walnut hulls on linen and silk fabric and wool yarn (no mordant)

Top: fresh walnut hulls

Below left: Frozen walnut hulls Below right: Dried walnut hulls



Focus on Tannin

In the third session of the one-year course at Ditchling Museum we concentrated on tannin-rich materials and their use as dyes and mordants and to create black with iron.

The three tannin-rich dyes we chose were all barks: elm bark, birch bark and cherry bark. For the tannin mordant we used oak galls and we tried two methods of creating black with ferrous sulphate and tannin from plants. We also sampled oak galls as a dye.

A tannin mordant is most commonly used on vegetable fibres, either alone or as part of the alum mordanting process when using alum sulphate or aluminium from symplocos leaves. Tannin is also used as a component in a dyeing method for animal fibres with some dyes and this method will feature in a later session.

Black can be achieved by a combination of tannin and iron but over time this method can damage fibres, especially wool, as it requires 25% iron (ferrous sulphate). There are many sources of tannin that can be used with iron to create black and we used oak galls in one method and alder bark and twigs in the other. When dyeing black using the tannin/iron complex the fibres must be alternately dyed then aired, in order for the depth of colour to develop. Exposure to the air is an important part of the process.

As I had anticipated, the barks gave very little colour on the vegetable fibres. We might have achieved stronger colours on all the fibres if we had been able to test the barks over a longer period of time. However, as we decided to to complete the processes within the time available on the day of the session, we followed the usual method of simmering the barks to extract the colour. The only difference from the usual method was that we added the wetted fibres and the bark to the dye pot at the same time, rather than simmering the barks first to extract the colour. This meant that the fibres were in the dye pot for longer than is the case if the colour is extracted first.

My preferred method of dyeing with tree barks is as follows: pour very hot water over the bark pieces and leave to soak for at least 24 hours – the longer the soak, the better. Then start to apply heat and simmer the bark for about an hour. Leave to cool and soak for a further 12 to 24 hours, simmer again for about 30 minutes then strain off the dye solution and add the fibres. Simmer the fibres in the dye bath for about one hour then leave to cool. In the meantime, the bark can be simmered again to extract more dye colour, which can be added to the first dye bath or used to make a second dye bath.

Barks can also be used following the alkaline extraction method described in an earlier post: More experiments with the alkaline extraction method. 

Alder cones (top) and Knopper oak galls (Photo by Liz Miller)

Knopper galls develop as a chemically induced distortion of growing acorns on pedunculate oak trees (Quercus robur), caused by the Andricus quercuscalicis gall wasp, which lays eggs in buds. (The name Knopper comes from the German word Knoppe, which is the name of a kind of helmet, and indeed it is as though the acorn has had a kind of helmet put on it.) 

Airing the dyed fibres from the tannin/iron dye bath (Photo by Ali Rabjohns)

Tannin/iron complex on cotton fabric and yarn Left: oak galls+iron Right: alder bark & twigs+iron (Photo by Ali Rabjohns)

The lavender shade is oak galls+iron on cotton fabric. The black colour is from alder bark and twigs+iron on cotton.

Left: Alder bark & twigs+iron on wool Right: oak galls+iron on wool (Photo by Fiona Eastwood)

Note: further simmering and airing should eventually give blacks with these tannin/iron recipes. 

Bark dye samples in the modifier pots (Photo by Fiona Eastwood)

Birch bark samples – Left to right: no modifier, +acid, +alkali, +copper, +iron Fabrics from top: linen, cotton, silk + some modifiers (no mordant) Below: alum mordant (Photo by Zuzana Krskova)

Cherry bark samples – As above but without the sample +alkali (Photo by Zuzana Krskova)

Elm bark samples – Details as above for birch bark (Photo by Zuzana Krskova)

Alder bark and twigs +iron (Photo by Zuzana Krskova)

Oak galls +iron (Photo by Zuzana Krskova)

More from the one-year course at Ditchling Museum

As we are following a similar programme to last year, much of the information will be available in earlier posts. So I will just outline our activities and only give more details of anything that is different from last year.

In October we started with substantive dyes and used rhubarb root (Rheum spp.), buckthorn bark (Rhamnus spp.) and walnut hulls (Juglans spp.). These were used without a mordant and with all four colour modifiers: acid (clear vinegar), alkali (soda ash), copper (copper water), iron (iron water). We used home-made copper and iron waters as I had them conveniently to hand but we could have made solutions from copper sulphate and ferrous sulphate as alternatives.

We used dried walnut hulls rather than the fresh green ones and, as the dried hulls tend to give paler browns, we added clear vinegar to pH4.5 to the dye solution in order to achieve deeper shades of brown. This is something I learned from Helen Melvin of Fiery Felts and it certainly results in deeper browns, so many thanks to Helen for the tip.

We also removed some of the samples from the solar dye pots we had set up at the first session in September.

Modifier pots with samples (photo by Fiona Eastwood)

Making copper water by soaking copper pipe in vinegar and water (Photo by Ali Rabjohns)

Rhubarb root and buckthorn bark samples drying outside (Photo by Fiona Eastwood)

Walnut hull samples drying (Photo by Fiona Eastwood)

The dyed samples are ready for assembling Left to right: buckthorn bark, walnut hulls, rhubarb root

(Photo by Jacqui Symonds)

Samples on various fibres from a solar dye pot using Coreopsis tinctoria with alum mordant (Photo by Kendall Clarke)


Resist dyeing techniques

One of the sessions on the one-year course at Ditchling Museum was devoted to resist dyeing techniques, specifically to cassava paste resist, used traditionally in Nigeria, and Dhabu or mud resist, used in India. For the cassava paste resist the students either applied the paste to the fabric with a brush or used zinc or tin stencils from Nigeria, which I have as part of my textile collection. The mud resist paste was applied to the fabric either with a brush or using carved wooden blocks.

The mud resist paste was bought from Saith Ffynnon Wildlife Plants (link on home page) and came supplied as a dry mixture for combining with water.

The following notes are from the information sheets I prepared for the students.

Resist Pastes

 Resist Paste Clay from India (Dhabu) – use according to instructions supplied with paste. Pastes from rice flour & cassava flour can also be used. (Cassava flour paste is used in Nigerian indigo dyeing.)

Cassava flour resist paste   

 This is traditionally used as a resist in Nigerian Adire  indigo dyeing. The Adire is either produced by free-hand painting of cassava paste, Lafun, onto the cloth or by stencilling the starch on fabric. The stencils are made from corrugated zinc or a perforated tin sheet.

Reference: Cassava flour resist paste

The extract below is from the reference above. My interpretation follows.

“For every 1kg of flour of any type used in the study, 4 litres of water or more was used for the preparation. Some of the flour was prepared under hot condition and stirred on fire for a quarter of an hour as prescribed by Wolff (1985); that long stirring of paste prevents lumps. For the innovation, not all the paste was able to stand long stirring on fire as prescribed. For example, the cassava flour and starch prepared on fire for less than 10 minutes became too elastic and tough to manage. It could not be forced through the mesh for the screen printing application and for the stencil; it was too heavy thereby breaking the linoleum carpet, plastic and even the indigenous metal stencil. For cassava flour and starch, the paste was prepared with hot boiling water but not on fire. The cassava starch powder was melted in ½ a litre of cold water before 3½ litres of boiling water was poured and stirred to form the paste. After stirring, the paste was shared into ¼ kg in different bowls and mordant (caustic soda) which was considered most appropriate in this study was administered. Normally among the young producers today, 2 tablespoons full of caustic soda is the practice for 1 regular plastic measure of flour (Ike ijoba), but in this study for proper documentation and standardized measurement of the chemical for studio practise and general production, the study shared the paste into manageable quantity. In every ¼ kg, the two identified activators were administered. Alum was turned into crystal to carry same texture with caustic soda, one levelled table spoon full of each were administered in different bowl of the prepared paste, while in another, one and half and the final one, two levelled table spoons.”

My interpretation of this:

Use 4 litres of water to 1kg cassava flour. For 125gms flour use 500mls water. Carefully blend the flour first in 100mls cool water. Bring the remaining 400mls of the water to boiling point and then gradually stir it into the flour mixture, stirring constantly to create a smooth paste. If desired, add about a teaspoon of alum sulphate, first dissolved in some of the boiling water. (I’m not sure why this is traditionally added. In some cases copper sulphate (called “blue alum”) is also added, probably as a preservative. I usually omit both alum and copper sulphate.) If necessary, strain the mixture through a sieve to make sure it is free of lumps. Note: I have no idea why the caustic soda would be added; it is certainly not a mordant. When I attended a course with a Nigerian dyer she added alum and “blue alum” (copper sulphate) to the cassava paste solution but was unable to tell me why she did this.


Printing with marigold flowers and gum arabic

Printing with marigold flowers and guar gum

Printing with symplocos paste

Mud resist dyeing

Resist printing in Rajasthan

Cassava resist dyeing

Cassava resist dyeing

Ross Belton applying Dhabu mud resist

Students applying cassava paste resist through metal stencils from Nigeria

Close up of one of the metal stencils

Dhabu resist

Cassava paste resist

All photos by Helen Gibbs

Ditchling Museum Natural Dyeing Course (5)

I’m afraid this is rather late as I’ve been seriously ill in hospital again and had to postpone the August session at Ditchling Museum.

This post should catch up on what we did at the last session before my illness, when we used madder, cochineal and weld. We followed the usual methods and prepared fibres with aluminium sulphate for wool and silk and aluminium acetate for cotton and linen. With madder and cochineal, we also used aluminium from Symplocos leaves as a mordant for all fibres. (See earlier posts for Symplocos mordanting details.)

WELD 100%

The colour from weld was extracted in the usual way, simmering it for about 30 minutes. When the dye liquid had been strained off and the fibres added, the temperature of the dye bath was kept just below simmering point to achieve clearer colours. We used both dried weld and fresh weld for comparison purposes.

 Photo by Zuzana Krskova

Weld dye bath

 Photo by Ross Belton

Dried weld results – From left above: linen, cotton, silk From left below: cotton & linen wool & silk, no mod, + acid, + alkali, + copper, + iron (All alum mordant)

 Photo by Ross Belton

Fresh weld results – From left: cotton & linen, wool & silk, no mod, + acid, + alkali, + copper, + iron (All alum mordant)

 Photo by Zuzana Krskova

Close up of some weld results – From left: cotton & linen, wool & silk, no mod, + acid, + alkali, + copper, + iron (All alum mordant)


The colour was extracted from the cochineal using the multiple extraction method described on p59 of Colours from Nature. For this method the same whole (or ground) cochineal is simmered three times and the extracted colour is strained and added to the dye bath after each extraction. The solutions from the three extractions form the dye bath. It is a good idea to strain the final solution through a coffee filter paper to remove any loose particles which might cause blotches on the fibres but we didn’t do this as we didn’t have the necessary equipment. The fibres were added to the dye bath and simmered for 30 to 45 minutes.

 Photo by Zuzana Krskova

Cochineal dye bath

(More cochineal photos to follow)


The chopped madder root was used according to the following recipe: first wash the madder in a sieve under running water for a few seconds. Then pour boiling water over it, leave it to soak for about 30 seconds and then strain off this liquid and put it aside for a second dye bath later. Repeat this process and add the strained-off liquid to the first liquid. Then put the same madder root into a pot and simmer it for about 30 minutes to extract the dye colour. Strain off this liquid which becomes the first dye bath. Allow it to cool a little, then add the fibres and leave them to steep in the dye bath for about 45 minutes. If a deeper colour is required, the dye bath can be heated for 30 to 45 minutes but keep the temperature below simmering point. Then allow the fibres to cool in the dye bath.

The solutions from the first two soakings give a second dye bath, which can be used either cool or heated as above. However, I’m afraid we produced no samples from this second dye bath as it was discarded in error.

This method of dyeing with madder differs from some other methods but usually gives clear corals and reds, depending on the strength of the dye bath and the length of time the fibres are in it. For really deep colours, it is often necessary to use 200% madder to dry weight of fibres, especially if dyeing vegetable fibres.

 Photo by Zuzana Krskova

Madder dye bath

 Photo by Ross Belton

Madder root – Top from left: linen, silk, cotton Below from left: From left below: wool & silk, cotton & linen no mod, + acid, + alkali, + copper, + iron (All alum mordant)

 Photo by Ross Belton

Madder root – Top from left: cotton, linen, silk  Below from left: wool & silk, cotton & linen no mod, + acid, + alkali, + copper, + iron (All Symplocos mordant)

 Photo by Ross Belton

Tannin is not necessary when using aluminium acetate and this was an extra experiment to see if using tannin before applying aluminium acetate improved the colours.  Unsurprisingly, it didn’t. Top: cotton, below: linen 

Ditchling Museum Natural Dyeing Course (6) – Woad, Japanese Indigo & Saxon Blue Day

Unfortunately I’ve been seriously ill in hospital again, so the August session at Ditchling Museum was cancelled and we used the September session to harvest and use the woad and Japanese indigo (Persicaria tinctoria) before it was too late in the season. At this session we also used Saxon Blue.

After we had used the woad and Japanese indigo leaves for blue, we simmered the same leaves to make a dye bath for tans.


One of the students brought some woad leaves, which were chopped and then we poured boiling water over them and left them to steep for about an hour. Then the liquid was then strained off  and the leaves squeezed well to extract all the dye potential.When the liquid had cooled to 50C, soda ash was added to turn the liquid from brown to green and the liquid was whisked until the froth became blue and then whisked further until it started to turn white again. We allowed the froth to subside and then added a reducing agent, sodium hydrosulphite, to remove the oxygen. When the liquid below the surface had become greeny yellow, the vat was ready to use.

NOTE: As woad is said to prefer soft water, it is a good idea to use rain water for woad vats. However, I rarely remember this and have always found the ordinary water from my tap produces a perfectly good woad vat. I have also read that the dye solution should be cooled quickly to 50C, so some people put the container of woad solution into a second container of cold water and sometimes add ice cubes to speed up the cooling process. This is not something I tend to do and my woad vats are always fine but they might be even better if I remembered to cool them down quickly.

Straining off the woad solution after the leaves had been steeped in the boiling or very hot water

Blue froth forming as the liquid is whisked

Results from the woad vat Left to right: cotton, wool, silk noil, silk fabric, cotton fabric, linen fabric with 2 wool samples

Results from the woad leaves simmered for a tan dye bath From left: NM wool, NM silk, NM cotton, NM linen, alum wool, alum silk, alum cotton, alum linen (NM = no mordant) Note: All the cotton & linen samples are actually pink, not blue, in tone


My Japanese indigo had already started to form seed, so the blue dye potential was reduced and the results were rather disappointing. Luckily, one of the students brought some of her own Japanese indigo leaves and we tried two methods – the usual vat method and the water and vinegar method.

In the vat method the Japanese indigo leaves are torn or cut up into small pieces, covered with cool to warm water and brought to simmering point over a period of about 1 to 2 hours. (Note that this differs from the woad method in that boiling water is not poured over the leaves, but they are first covered with cool to warm water and then heated gradually.) The leaves are then left to steep in the hot water for about an hour. Then the liquid is strained off  and the leaves are squeezed well to extract all the dye potential. When the liquid has cooled to 50C, the dye vat is then made in the same way as described above for woad. 

Cutting up the Japanese indigo leaves

The cut leaves

The water and vinegar method requires at least 200% fresh leaves and this method gives blues which may be less stable or permanent that the blues from the more traditional methods of dyeing with woad/indigo. However, this method requires only water and clear 5% vinegar. The vinegar should be added at the rate of about 15mls clear vinegar per litre of water. Harvest the leaves and process them immediately. Chop or cut up the leaves as finely as possible, preferably not using a wooden chopping board, as this may absorb too much of the precious dye solution, or process them with a little water in a liquidiser. Put the chopped leaves into a container and add enough water to cover them. Then add the vinegar and knead the leaves very well for at least 5 minutes until the liquid is bright green. Strain off the liquid and set it aside. Knead the leaves again in water and vinegar as before, strain off this liquid and add it to the liquid reserved from the first kneading process. Immerse the fibres immediately in the liquid and leave them to soak for about one hour. Then rinse them in clear water and air them. Finally, add a small amount of fibres to the liquid and leave them overnight to exhaust any remaining dye potential, then rinse and air them.

NOTE: I have read that some dyers use iced water without the addition of vinegar but I have not tried this.

This shows the fibres being immersed in the water/vinegar Japanese indigo solution (Photo by Ross Belton)


Saxon blue or sulphonated indigo is an indigo extract made by dissolving indigo powder in sulphuric acid. The process was discovered around 1740. It is called Saxon Blue because the blues it produced resembled the blues of ceramic wares based on cobalt and Saxony was the centre of that industry.

Saxon Blue is used mainly for dyeing wool and silk and produces blues with a turquoise tone. Blues from Saxon Blue may be less fast to light and washing than indigo blues made by the vat method and deep blues from Saxon Blue have higher levels of fastness than paler shades. There is some disagreement about whether an alum mordant is needed for Saxon Blue. I tend to prefer to use an alum mordant, as this seems to produce deeper, clearer blues.

Saxon Blue is simple to use. Prepare the hot water for the dye bath and then just stir in some Saxon Blue liquid. How much one needs to use depends on the depth of blue required and the amount of fibre being dyed. I usually start with one or two teaspoons and then add more if necessary. Then add the fibres, bring the dye liquid up to simmering point and simmer gently for 30 to 45 minutes. Then leave to cool before rinsing.

The Saxon Blue we used was bought from Fiery Felts (see link under Useful Websites) and made by Helen Melvin. This gives excellent blues and a little goes a long way.

This shows some results on silk: top – Saxon Blue, below left – Japanese indigo vat method, below right – Japanese indigo water & vinegar method (Photo by Ross Belton)

More about Symplocos leaves as a mordant

Following on from my recent experiments with symplocos leaves as a plant source of aluminium for mordanting, I have done some further tests, mainly to try this plant mordant out on silk and cotton fibres.

After my last tests, I re-used the 50% symplocos mordant solution on a further wool skein to test whether the solution would still be viable as a mordant and I was pleased to note that, when I added a sample to madder and logwood dye baths, it produced a strong colour. This suggests that the 50% mordant solution could safely be re-used on a further batch of fibres.

This led me to wonder whether symplocos would still work if used at a lower percentage, so I decided to use 30% instead of 50%. I also decided to see whether the 30% mordant solution could be used more than once.

The main difference between mordanting animal fibres and vegetable fibres with symplocos leaves is the temperature at which the fibres are treated. Wool fibres are heated slowly to simmering point, held at this temperature for about an hour then cooled and rinsed. Vegetable fibres and silk are treated in a hot solution (60C/140F) but not simmered. The vegetable fibres must also first be treated in tannin.

I prepared two sample sets, each consisting of wool, silk and cotton fibres, and I treated the cotton fibres first in a tannin solution from oak galls. I then weighed the sample sets and worked out the weight of symplocos leaves I would need for 30% weight of fibres (WOF).

To prepare the symplocos mordant solution for all fibres, I simmered 30% symplocos leaves in water for about 45 minutes then strained the solution through a piece of very fine muslin cloth. At this point I saved the used leaves and re-simmered them, so that I could add this solution to the exhaust mordant bath after my tests and then use this on a further batch of fibres.

I divided the symplocos leaf solution into two pots – one for cotton and silk and the other for wool.

I slowly heated the mordant bath containing the wool to simmering point then held this temperature for about one hour. I then removed the pot from the heat and left the fibres to cool down.

The cotton and silk mordant bath was heated to 60C/140F and then removed from the heat. The fibres were then left to soak in the solution for about an hour.

I then dyed the fibres in madder and logwood dye baths.

The photos below show the results from the madder extract and logwood extract dye baths.


Left from top: 30% symplocos first mordant bath on cotton, silk, wool

Right from top: re-simmered leaves + exhaust mordant bath on cotton, silk, wool

Centre below : no mordant, 10% alum mordant


Left from top: 30% symplocos first mordant bath on cotton, silk, wool

Right from top: re-simmered leaves + exhaust mordant bath on cotton, silk, wool

Centre below : 10% alum, no mordant

From these tests it seems that using the symplocos leaves at 30% WOF gives good results but that re-using the 30% solution may produce paler shades on some fibres, which could be less fast. Although 30% WOF works well on the first batch of fibres, I think it might be better to use 40 – 50% WOF if one intends to re-simmer the symplocos leaves and to add the solution to the exhaust mordant bath for re-use.


Symplocos leaves as a source of aluminium mordant

Some plants are aluminium accumulators and can be used as an alternative source of alum for mordanting. Among them are clubmosses and I have written in an earlier post about how clubmosses were used in the past as an alternative mordant.

Another alternative source of alum comes from the leaves of  species of Symplocos. The leaves of Symplocos racemosa are used in parts of India as a source of aluminium mordant and in Indonesia Symplocos cochinchinensis is used in a similar way.

The Bebali Foundation is the organisation behind The Plant Mordant Project which aims to empower women in Indonesia by building partnerships for sustainability with rainforest communities and indigenous textile artists; the sale of dried Symplocos leaves for mordanting is part of this project.

The website provides a wealth of further information on this project and also gives details of where to buy the powdered leaves and how to use them. This extract from their website explains the work of The Plant Mordant Project.

“The Plant Mordant Project offers natural dyers a unique opportunity to avoid mordants produced by industrial processes and make reliable colors 100% from plants. Powdered leaf from Symplocos trees can replace alum in conventional natural dye recipes and produce some exciting new colors. Natural dyers already chose plant dyes over synthetic dyes because they are aligned with their values, and the Plant Mordant Project offers an opportunity to extend the expression of these values by also using a plant-sourced mordant. 
At its source, the Plant Mordant Project builds partnerships for sustainability with rainforest communities and indigenous textile artists in Indonesia. Through its sourcing and sales of Indonesia’s traditional plant-sourced dye mordant, the Bebali Foundation ( alleviates rural poverty and empowers women, saves rainforests, and supports the traditional textile arts. The Bebali Foundation brings to this project a decade of experience in the fields of conservation, indigenous culture, and rural livelihoods, while its partnerships with the Royal Botanical Gardens at Kew and the Indonesian Forestry Department, and its funding from the Ford Foundation bring world class scientific rigor and accountability.

I recently purchased some dried symplocos leaves from Couleur Garance in France and have begun to experiment with them. (

Symplocos leaves can be used on all fibres; so far I have only used them on wool and I am pleased with the results. One thing to bear in mind is that Symplocos leaves also yield a yellow dye, so the yellow colour of the mordanted fibres may have an effect on the colours achieved from the dye pot. However, I found the colour difference on madder-dyed wool when compared with wool dyed on a traditional chemical alum mordant was very slight.

I used the powdered leaves at the rate of 50% weight of the fibres and simmered them in rainwater for about 30 minutes until they sank to the bottom of the pot. I used rainwater because the recipe stipulated “soft water” and I live in a hard water area. I then strained off the liquid and allowed it to cool to 40C as directed.

I washed the wool thoroughly and then soaked it in a weak solution of washing soda (soda ash) as directed in the recipe. (I suspect this washing soda soak is probably more relevant for use in areas where dyers may not have easy access to other wool washing materials. The important thing is to make sure the fibres don’t have any grease or dirt adhering to them.) I then added the wool to the cooled mordant solution and slowly raised the temperature to simmering point (95C) over a period of one hour. I allowed the solution to cool then removed the fibres and rinsed them. The fibres were a medium yellow colour, although the recipe said they would be a”pale shade of yellow”.

In order to be able to compare the effectiveness of Symplocos leaves as a mordant, I added samples mordanted with two other types of alum mordant – 10% aluminium sulphate and Kaltbeize AL, a cold mordant of aluminium formate, which I have written about in previous posts. I also added three further samples – two mordanted with different sources of tannin – blackberry leaves and shoots and oak galls – and one treated with rhubarb leaf solution.


This photo shows from l to r: 10% aluminium sulphate, Kaltbeize AL cold aluminium formate mordant (see a previous blog post), blackberry leaves, oak galls, rhubarb leaves, symplocos leaves

I then dyed all the skeins shown above in a madder dye bath.
The photo below shows the madder-dyed skeins in the same order as the undyed skeins above.
The photo below shows more clearly the difference in shade between the three types of alum mordant. The symplocos-mordanted skein is the third one from the left and it is only very slightly more orange in tone than the skeins from the other two alum mordants.
The second skein may appear slightly paler than the first skein but this is because the wool used for the second skein is more loosely spun and this may have caused the slight colour difference.
 My conclusion from this first experiment using Symplocos leaves as a mordant on wool is that they provide a useful alternative source of alum for mordanting, especially for those dyers who prefer to avoid manufactured chemicals and to use only plant materials. The colour obtained from madder on wool using a Symplocos mordant is virtually the same as the colour from an aluminium sulphate mordant and the initial yellow colour of the mordanted fibres seems to have an insignificant effect on the colour obtained.
I used the remaining Symplocos solution to dye two wool skeins an attractive shade of yellow but I intend to experiment with them to see if the remaining solution also contained enough aluminium to have a mordanting effect.

More thoughts on the 1-2-3 lime/fructose indigo vat

I have been looking at various recipes for the 1-2-3 lime/fructose indigo vat, which was developed by Michel Garcia, and I made one interesting observation – in most of the recipes, the fructose (which is the reducing agent) is added before the lime (calcium hydroxide), which is the alkali. This surprised me as, when making 1-2-3 vats, I always add the alkali first. I wondered whether I was alone in this, so I was pleased to find that in Helen Melvin’s recipe the alkali is also added first. Helen is a very experienced dyer, with extensive practical knowledge of various types of indigo vats, and she has also attended courses led by Michel Garcia, so I felt I was in good company.

So why should I be surprised to find so many recipes in which the reducing agent is added before the alkali? Firstly, because it goes against what is, I think, the usual practice when making indigo vats; for example, when making an indigo stock solution, the alkali, in this case caustic soda, is added before the reducing agent; and when processing fresh woad leaves to make a vat, the alkali is added to the solution before the reducing agent. Indeed, the alkali is added first when making most types of indigo vats, so why would one change this order? The other reason why changing the usual order seems to me illogical lies in the name “1-2-3” vat, which seems to me to suggest that one would first add to the water one part indigo, then secondly one would add two parts lime (calcium hydroxide), the alkali, and thirdly three parts fructose, the reducing agent, thus maintaining the neat 1-2-3 order of both the proportions of ingredients and the order of adding them. (And also adding the ingredients in the same order as with other types of indigo vat.)

So does it actually make any difference whether one adds the alkali or the reducing agent first? One way to find out would be to do some experiments, so I made two small sample vats, for one adding the ingredients in the 1-2-3 order and for the other adding the ingredients in the 1-3-2 order. Otherwise, exactly the same weights of ingredients were added to each vat.

The photos below show the results. In each of the photos, the 1-2-3 order vat is on the left and the 1-3-2 order vat is on the right. The photos show the gradual progress of each vat and the final test samples. The vats each took about 1 hour to be ready for use.

The results indicate that the order in which the ingredients are added seems to make little, if any, difference to the final results. Although the vats didn’t look exactly the same at each stage, the dyed samples show that each vat produced samples of almost identical shades of blue. So I shall continue to add the ingredients in what seems to me to be the most logical order: 1-2-3.

For further information on indigo vats, see Helen Melvin’s excellent book “Indigo; The Colour of the Sea and Sky”, available from Helen at Fiery Felts (link on the right under “Useful Links”).

More Skeins for Ditchling Museum

A couple of weeks ago I dyed a final set of samples for the Ethel Mairet project at Ditchling Museum of Art and Craft, following recipes in the 1916 edition of “Vegetable Dyes”.

Below are the details of the recipes and the results.

Samples of wool and silk were dyed following the instructions on p 103 Recipe no. 7 for MADDER Red for silk

A cold 25% alum mordant was applied and the fibres were allowed to soak in the cold alum mordant solution for 24 hours. 50% madder was placed in the dye pot, together with a handful of bran tied into a muslin bag, and water was added. The fibres were rinsed and then added to the madder dye bath. The temperature was raised gradually to just below a simmer, the heat was turned off and the fibres were then left to steep in the dye bath without further application of heat. When the dye bath was getting cool, heat was again applied until a simmer was reached. The heat was then turned off and the fibres left to steep overnight. They were then removed, rinsed and washed.

Further samples of wool and silk were mordanted with 2% copperas (iron) and dyed as above, as suggested in the above recipe for brown shades.

From the left: wool, silk, wool for brown, silk for brown

Samples of wool, silk, cotton and linen were dyed following the instructions on p110 Recipe no. 1 for WELD  Yellow for Silk

Wool and silk fibres were mordanted with 25% alum sulphate and the cotton and linen fibres were mordanted with 5% alum acetate. 200% weld was simmered for 15 minutes then the dye liquid was strained off into a dye pot and left to cool. When it had cooled a little, the silk and wool fibres were added and left to steep in the dye solution. They were then removed. The weld was simmered again with the addition of 2 teaspoons of soda ash and this solution was then strained and added to the first dye solution. The dyed fibres were added to this solution and allowed to steep until they had achieved a suitable depth of colour.

From the top: wool, silk, cotton, linen

Samples of wool and silk were dyed following the instructions on p121 for DYER’S BROOM

The fibres were mordanted with 25% alum sulphate. The dyer’s broom was simmered for 45 minutes to extract the colour, then strained. The fibres were gently simmered in the strained dye solution for 45 minutes and left to cool in the dye liquid. They were then removed, rinsed and washed.

From the left: wool, silk

Samples of wool, silk, cotton and linen were dyed following the instructions on p125 Recipe no. 9 for CUTCH Brown for Wool

The fibres were not mordanted. 15% cutch extract was dissolved in boiling water then gently stirred into a dye pot of water. The fibres were added and simmered in the solution for about an hour, then left to cool for a while.  2% iron (ferrous sulphate) was dissolved in boiling water then added to a pot of water. The cutch-dyed fibres were added to the iron solution and simmered for 15 minutes. They were allowed to cool, then rinsed and washed.

From the left: wool, silk, cotton, linen

Samples of wool, silk, cotton and linen were dyed following the instructions on p139 Recipe no. 8 for GREEN WITH INDIGO EXTRACT & WELD FOR WOOL.

Wool and silk fibres were mordanted with 25% alum sulphate and the cotton and linen fibres were mordanted with 5% alum acetate. They were first dyed blue using indigo extract (Saxon Blue). The fibres were simmered in this indigo solution for about 45 minutes then allowed to cool a little. The weld dye bath was prepared by simmering 100% weld to extract the colour. The solution was strained off and the indigo-dyed fibres were added to the weld dye bath and simmered for about 45 minutes. They were left to cool in the dye bath, then rinsed and washed.

NOTE: Although this recipe is specifically for wool, it was used on this occasion to dye all four fibre types. However, as noted by Ethel Mairet, indigo extract is less suitable for cotton and linen and these fibres did not take up much blue dye. The silk reacted better but the depth of blue on the silk was still less than that on the wool. This meant that the greens achieved were less blue and more yellow in tone.

From the left: wool, silk, cotton, linen