Isabella Whitworth

probably more than natural and synthetic dyes, wax, resists, and history


Teaching News


Wax resist and steam-fixed dyed scarf. Silk crêpe de Chine. Isabella Whitworth, 2016

I’ve just unpacked after teaching three one-day courses in Oxfordshire. This completes my teaching programme for the year. I teach regularly at only two venues: Ardington, south of Oxford, and West Dean, just north of Chichester.

Ardington School of Crafts is non-residential. My courses there are always one-day, although sometimes linked so that students studying, say, natural dyes can take a further course focusing on indigo. They are suitable for complete beginners. Ardington’s 2017 programme will shortly go ‘live’, and the six dates are on my teaching page here. There will be a variety of courses, all of them repeating popular subjects.

West Dean College is residential, although some students make their own accommodation arrangements. Courses stretch across a few days, have up to now taught resist techniques using synthetic dyes on silk, and have been for beginners and intermediate students.

Many students have attended several of my courses and have progressed very well. After discussions with the Short Course Organiser at West Dean, we have added a new course which will take place from April 24th – 27th 2017. Its title will be Handpainted Silk Scarves: Developing Design, Building Technique. This course is designed for those who have relevant experience gained with me or other tutors, but would like to study or practise techniques and ideas not viable on beginner / intermediate courses. Some of the focus will be on design and planning. The idea is to offer more experienced students a course of their own.

However, all students, of whatever experience or ability, continue to be welcome on my beginner / intermediate courses. Although I may be instructing beginners too, more experienced students know they can progress at their own pace within the structure of the course and I can assist them in new directions.


Inside a vat made from Japanese indigo (Persicaria tinctoria)

West Dean Summer School takes place over three weeks with a separate set of courses each week. I will be teaching a six-day Summer School course from August 5th – 12th 2017 titled Creative Dyeing for Scarves and Fabric. This course will be suitable for beginners, intermediate students and anyone who has studied with me before. My idea for Summer School is to broaden understanding of resist techniques, such as shibori and wax resist, by exploring some relationships between traditional and contemporary dyeing. The course will feature a natural indigo vat which can be used as well as (but not together with!) synthetic dyes. Indigo has a unique and beautiful affinity with resist techniques, and many contemporary resist processes are based on its traditional use. There will also be opportunities to discuss and develop designs for wax resist work. More details will appear on the West Dean website.

Teachers and technicians can apply for a 50% discount on a Summer School. Contact West Dean on 01243 818300 to register your interest, with the name of your school, college or university, and a 1st, 2nd and 3rd choice of Summer School course. BUT please note that booking for Spring and Summer 2017 at West Dean is not available until November 2016.

My February 2017 course is full.


Ardington School of Crafts

West Dean College


Mordant Pastes 2

Recently I wrote about experimental work I’ve been doing with a colleague, using mordant pastes. See here to read the post. I recently completed a batch of work using the pastes and combining them with wax resist. All work is on silk crêpe de Chine.



Testing Times 1 & 2

Testing One

I have many friends who take an interest in my pots of goo and occasionally they send me things. One such friend returning from Essaouira sent me pigment she had been sold as ‘shellfish purple’. Historically, the Moroccan coast was an area much involved in the making of this fabled dye (also known as Imperial Purple and Tyrian Purple) but I expressed doubt that what she had sent was ‘the real thing’ because it is fabulously expensive to produce even a small quantity. Just 5 grams costs around £450.00. But I thought it would be fun to try dyeing with it.


Green grains and finished colour on silk

I took advice from a specialist colleague, Professor Zvi Koren of the Edelstein Center for the Analysis of Ancient Artefacts (link below). He advised that shellfish pigment is not water-soluble, so that by adding just water I would not get a true solution: I’d get a reddish coloured mixture with the pigments dispersed but not dissolved. I added water and the grains went bright pink. Very bright indeed, as you can see below.


The colour of the grains in solution: testing pH


Reduced liquid with lumps of dye matter

Following my colleague’s advice, I reduced grains in a hydrosulfite / dithionite bath in an alkaline solution, at about 60 C. The liquid went completely clear, with the dye matter gathered in lumps. This didn’t look right at all for shellfish purple, which should change to a greenish colour (as with indigo).  Nevertheless, I dipped silk into the clear mixture and it came out a bright pink – which does not wash out. So it’s certainly a dye, but certainly not shellfish purple.

Two other pointers to its not being shellfish purple: the Essaouira grains are green, and they shouldn’t be. There’s no snail pigment that colour, according to my colleague. It’s usually dark, blackish, brownish, purplish or violetish, but never green. And on top of that, the grains should have a yukky fishy smell. The Essaouira grains smelled vaguely of incense.

So this was a fascinating experiment, a story echoing many historical tales of dyes that were not as they claimed.

My thanks to Professor Zvi Koren of the Edelstein Center for the Analysis of Ancient Artifacts for his input and advice on testing the Essaouira grains.

Friends: please don’t stop sending me interesting things. But as an H&S caveat, pigments and grains bought in faraway places may be toxic or otherwise harmful so you need to be aware of handling and storing them. They are not necessarily what they say on the tin.

Testing the Other

At a recent course at West Dean my Old Geyser of a fabric steamer developed a problem. The thirty-year old steamer assembly consists of a standard water boiler (the sort to be found in every village hall), a custom-made stainless steel chamber, lid, and perforated base plate. Silks are rolled in paper and stacked upright inside the steel chamber. Water is heated in the boiler, the steam circulates and the combination of heat and damp sets the dyes. The water isn’t held at a constant boil but needs to come up to the boil – and hold it – every two or three minutes, for around two-and-a-half hours.

Only, at West Dean, it didn’t. The boil was less frequent than usual, and was held for shorter periods. I was concerned that dyes were insufficiently fixed and suspected a problem with the thermostat. (I should add that West Dean supply a professional Uhlig steamer, but I have always used mine, which holds more silk).

Back home, phone calls revealed that a new ‘simmerstat’ is what I required. But during the time since I bought the boiler, Brussels has dictated that EU citizens are insufficiently responsible to handle dangerous pieces of equipment that boil water. (Those in favour of Brexit might enjoy the link at the bottom of the page). A catering boiler will no longer come to a full, constant boil. My new simmerstat was fitted by the technical department, but the gaps between boils seemed longer than I remembered…. or was I just being twitchy?

I then discovered that a secondhand Uhlig steamer was on sale, owned by an ex-student. I couldn’t believe this piece of luck – and bought it. It is a solid, stable and well designed piece of equipment, although as with the West Dean one, it does not hold as much yardage as Old Geyser. In the Uhlig I tested several pieces of silk, including three blues which have a tendency to run if steamed sufficiently. No run-off.


Some runoff may be expected in initial rinses after steaming if heavily concentrated dye is used. Thereafter the water should run clear


Samples of identically dyed silks steamed in two steamers to compare colour and runoff

I tested identical blues in the mended Old Geyser. It now appears to be working well too – so I now have two working steamers. No recycling tip for Old Geyser: he threw a steamy party.


Where to buy shellfish purple in 2016? Here

Brexit? Pulling the plug on high speed kettles here

The Edelstein Center for the Analysis of Ancient Artifacts here




Mordant pastes

The work I’m briefly describing here is an offshoot from a joint project. I have been researching mordant pastes (as taught by Michel Garcia) with a dyer friend; eventually we will write up our work because it isn’t yet finished. But the work we have done has made me wonder if it wasn’t the key to finding a satisfying, creative way to use natural dyes in combination with wax resist. This has been an ambition of mine since I went to ISEND* in 2011. It’s there I first came across Michel Garcia, on whose generously-shared research our mordant paste work is based.

There are technical problems in trying to combine paste with wax resist. Wax melts in the vat if it’s taken above a certain temperature, and each dye needs at least some heat to fix it. Cold dyeing isn’t an option: it would all take too long. The dyes must take their place in an ordered sequence for colour. The pH of one vat can affect colour of dyes in another layer, the wax can begin to flake off, etc. If the indigo dips are included, there may be as many as 20 operations to create one scarf, as they did in the image below. So it’s time consuming and isn’t going to produce a low-cost item, but I feel I’m getting somewhere at last. The dyes used are weld (Reseda luteola) from a British source, and indigo (a mixture of Devon-grown Persicaria tinctoria and imported powder from Tamil Nadu). The different paste resists give different shades of yellow on the base layer, including the brownish colour visible in small, thin lines and spots which came from the iron in the mordant paste.

Follow up post in July 2016: see here.


Mordant pastes (iron, alum and titanium) on silk crêpe de Chine. Weld immersion-dyed; wax resist, indigo-dyed, wax resist and multiple indigo dips

* ISEND: International Symposium and Exhibition on Natural Dyes, La Rochelle, 2011. You can download information about this here

A little about Michel Garcia’s technique here



Patterns of Spain


The ceiling of Santa María de la Almudena, Madrid, designed and painted by José Luis Galicia. See link to an article at the bottom of the page


In the last few weeks visiting Spain, I discovered that I am not a fan of the selfie stick. With their backs to the magnificence of Seville’s Alcázar, Córdoba’s Mezquita and the courtyards of Granada’s Alhambra, endless troupes of tourists raised selfie-sticks towards themselves like fishermen without a pier.

Selfie-takers don’t always appear to study, or even enjoy the wonders they visit.  Their eventual aim seems to transmit images of themselves in front of the site. I’ve never seen selfie-takers at municipal dumps or eyesores so the desirability of a transmitted selfie must rely on the reputation or perhaps, newsworthiness of the backdrop: sightseeing is not essentially about looking at, or understanding, where you are. It seems to be about telling everybody what a great time you are having while you take your selfies. Each set of shots is followed by scrutiny of phone and images and it can all take a very long time, especially if you are there to see what they are in front of. We are living in a peculiarly self-obsessed world and I don’t ‘get’ the selfie thing at all: in fact, it makes me sad.

I’m getting on a bit and still like to sit and look at things. Sometimes I take photos, and nothing beats drawing as long as I’m not messing up the view for other people. Drawing ensures I’m ‘there’ – like nothing else. I’m dangerously near sounding smug, so I’ll just put up a selection of sketches and drawings from the trip. I’ve chosen ones related to pattern, or textiles and am avoiding pictures everyone knows. It’s a fairly random selection, so please excuse lack of coherence.


The Feast of the Immaculate Conception

The 8th December is the day of the Feast of the Immaculate Conception, which is a public holiday in Catholic Spain. Checking my Twitter feed that morning in Córdoba, I learned from the Reverend Richard Coles’ feed (@RevRichardColes) that blue liturgical vestments are permitted, by Papal decree, on 8th December in Spain. They are not worn on any other day of the year. I looked in on a Mass to see if he was right (he was), but did not take a photo. I idly wondered if the Papal decrees might be the result of lobbying by medieval woad or indigo dyers, so I checked on their dates. They were all granted in the late nineteenth century so I think it most unlikely.

Below is one of the elaborate statues of the Virgin Mary brought out for the feast day. She has a richly embroidered blue velvet robe and cloak. At the time I made no note of the lovely church where I saw her but the wonders of the internet reveal it to be the Iglesia Conventual del Santo Angél.


Blue is the traditional colour for the Virgin Mary. This statue is from the Iglesia Conventual del Santo Angel, Córdoba

The Banner of Fernando III 

During my visit to Seville, I of course went to its much-fêted Cathedral. I was completely unmoved by its vastness and found the building architecturally incoherent and not at all uplifting. I am not religious, but I can still be moved by a religious building and I found this one too big, too twiddly and too opulent. The enormous tomb reputed to contain the remains of Columbus is set within the Cathedral (yes, the selfie-takers were in front of it too).

The Giralda  was more interesting. This huge tower, started in 1184,  was once the minaret of the mosque originally on the site of the Cathedral and the climb to the top comprises 35 sets of ramps, built so that a horse could be ridden to the top to the top. It is set on the edge of the extensive Cathedral courtyard, with groves of oranges trees still in fruit when I went. I found the space peaceful despite the crowds there, and more moving than the Cathedral itself.


Banner of Fernando III, raised from the minaret of the mosque on its capitulation in 1248. Cathedral of Seville

What really engaged my interest within the Cathedral was a glass-topped case at the  west end. It contains the banner of Fernando III (later canonised as San Fernando). The banner has great historical importance as not only did it symbolise the capitulation of the Moors at Seville in 1248, but also united the heraldic arms of Castile and León for the first time. The original banner was made in the first half of the thirteenth century of pieced and embroidered silks. In the 1990s it was found to be in an exceptionally poor state of repair and urgent conservation was undertaken. Information suggests that conservation rather than restoration took place,  but I’m curious about the brightness of some yellow areas because it would be normal for most yellow dyes to have faded over 700 years.bannerfIII The inset image shows a diagram of the original design of the banner but is very poor quality because it was taken through glass at a difficult angle. The original colours are listed as red, yellow, purple and silver.

The link to the Instituto Andaluz del Patrimonio suggests that some dye analysis was done during the conservation work in 1999. I have yet to find a published paper on the findings. Naturally, I am curious about the purple dye (a colour associated with high status), which was used for the appliquéd lions. It’s unlikely to be orchil, which would have faded to beige by now, but as it’s hard for a casual visitor to see  what fabric is original and what is restored, who knows? It was a little frustrating to see many textiles displayed in church or cathedral treasuries, such as the Chinese-inspired vestment seen in Ronda (see top of page) with no explanations, details, dates, provenance etc.

Spain, though, is an amazing country for its visual inspiration, its history, buildings, landscape and wildlife. I just love Spain. But I need to improve my Spanish before I go back: I’m working on it.


The controversy over paintings in the Almudena Cathedral, Madrid here

The Giralda Tower, Seville here

Article in Spanish on the Banner of Fernando III here

Statement on the conservation of the banner by the Instituto Andaluz de Patrimonio Histórico here

Blue Vestments: clearly a subject of some discussion within the Catholic Church; check the comments beneath this post












Blue and Black

Indigo pigment

I’m trying to use my Japanese indigo (Persicaria tinctoria) before frost hits and kills it, and it won’t be long. I planted it late this year and have only managed 5 ‘picks’ which were made around 15 days apart, to allow for regrowth. I had enough prepared work to dye in the first vats, but for the last two ‘picks’ there was nothing ready. Not wanting to waste the precious crop I have endeavoured to make pigment, which basically involves reducing (by evaporating) the indigo, in its alkaline, oxygenated state, down to a thick paste, and then powder. This can be reconstituted into a dye vat at a later date.

A friend helped me with basic instructions but mostly I had to experiment. I probably wasted some indigo because I didn’t find a way of filtering efficiently. There also seems to be more leaf material in it than I hoped as it looked greeny-blue at paste stage. In a hot, dry climate like India shallow containers of liquid evaporate fast but here it took days, even on the top of the central heating boiler. It was a race to evaporate the goo before it went mouldy. I forgot to weigh the leaves but I think there was about 1 kg, which reduced to 5.3 grams of indigo pigment. There is a full explanation of the way I process Japanese indigo before the evaporation stage here so I won’t repeat the method.

Bideford Black

With pigment-making on my mind, I went to see the new exhibition at the Burton Art Gallery and Museum at Bideford. It’s called Bideford Black: The Next Generation and it centres on a rare and beautiful black earth pigment which emerges from the North Devon cliffs. In the past ‘Biddiblack’ (as it was known), has been used in paint manufacture, for making mascara, camouflaging military vehicles, in boatbuilding etc., and commercial mining for it continued until 1969. Artists working in a traditional manner, or with traditional materials, have valued its velvety dark strength and subtle tones. I had a chance to try it in the Burton Gallery last week, as can all visitors to the show. Bideford Black: The Next Generation is an unusual and unconventional exhibition and it’s certainly not traditional: participating artists responded to the pigment in diverse and often thought-provoking ways. Links below.

I wanted to find out if the pigment could be painted onto sized cloth and the exhibition organisers offered me some Bideford Black to take home and try out. Using a rare pigment 300 million years old was moderately inhibiting and my efforts also felt stuffy and old-hat after seeing the exhibition. Nevertheless, stuffy and old-hat is what I do, so I got on with it.

Using the soya milk recipe generously published online by John Marshall (see link below) I stretched and sized silk and cotton and worked experimental pieces. I wasn’t trying to make anything, just seeing what the pigment would do. The black was initially ground in a pestle and mortar and then mixed with more soya milk as a binder. I found that a small amount of gum arabic assisted in holding it together, stopping moisture bleeding outwards from painted shapes. The fabrics now need to cure.

Finally in this tale of blue and black, I was lucky to book a place on a monoprint workshop run at The Burton by Grizel Luttman-Johnson. We inked up perspex plates with Bideford Black printing pigment, which Grizel had prepared by grinding and mixing the Black with a binder and linseed oil. We then placed paper on the inked plate and made drawings on the reverse of the paper. Pressure caused ink to be picked up and an impression made on the front of the paper. The plate could be used again to pick up a ‘ghost print’, which created a kind of negative image. It was a very enjoyable day, well-led by Grizel.

Some links to the Blog for Bideford Black: The Next Generation 

The Geology of Bideford Black

The Nature of Black

Next Generation: Artists Selected

Launch and work information

Related links

Teachers’ Resource on North Devon Minerals

Grizel Luttman-Johnson

I am indebted to Michel Garcia and John Marshall for their freely published information:

Information on Michel Garcia’s DVD on natural dyes here

John Marshall instructions for making soy milk here