Isabella Whitworth

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


A Purple Pursuit

Orchil: For a few years I have been researching a (mostly) nineteenth century archive relating to a Leeds dye manufacturer. The early fortune and later success of this Leeds company were built on the manufacturers’ skill in the making of a dye called orchil. Orchil is an ancient dye, made from lichens of several varieties, and it dyes silk and wool various shades of purple. It does not need a mordant, a fact that was valuable to the historical dyer as it omitted the expense in the mordant process, and additionally avoided any harshening which mordanting can impose on silk. Purple could normally be achieved with natural dyes only with overdyes, such as indigo over cochineal, but orchil ‘got there in one’.

In its clearest and most beautiful form, orchil dye will give a glorious fuchsia colour and the clarity of this shade is assisted by the purity of the ammonia in which dyestuff is prepared. Historically, orchil was known to impart a freshness and bloom in ‘bottoming’ other dyes – e.g. when used as a base before overdyeing. Orchil was a much used and valuable dye throughout history, although its use is sometimes an enigma. It is often found in costly tapestries, which is surprising as orchil is not at all lightfast – a fact that was well-known.

With the advent of synthetic dyes in the later nineteenth century the use of orchil began to decline. Records in the Leeds archive indicate that large sums of money were still tied up in stocks of lichen in the 1870s and in trying to comprehend the place of orchil in the nineteenth century I found the archive inextricably linked to the history of the colour purple. We will publish in due course but an extract from the abstract of my co-authored paper with Professor Zvi Koren at DHA 32 offers a clue:

One of the more astounding discoveries associated with this archive was that it included a small envelope signed by Charles Samuel Bedford declaring the content of the packet to be ‘Tyrian Purple’. But what was really inside the envelope? Was it truly Tyrian Purple…?

Shellfish dyes: Much has been written on the history of the shellfish dye Tyrian Purple (Imperial Purple, The Purple of the Ancients, murex etc) and its association with wealth and status. There is a lot of utter rubbish online about Tyrian Purple, so beware if you are researching and look for reliable sources, such as those listed in Chris Cooksey’s Tyrian Purple Bibliography, linked below.

Nucella lapillus shells, Somerset

Nucella lapillus shells, Somerset

For the purposes of this particular post, it’s important to realise that long after the method of shellfish dyeing* was lost, probably around the fifteenth century, the reputation of purple as a high status colour lived on. Purple retained a kind of status independent of its original connections to shellfish dyes. There are contemporaneous references to shellfish dyeing (e.g. in Vitruvius, and Pliny the Elder in his Natural History) and something has always been known of the preparation process, although modern interpretations of commentaries vary.

Since the mid nineteenth century chemists, scholars and dyers have researched shellfish dyes and the ancient dye process has been patiently and painstakingly rediscovered. Shellfish dyeing can again be undertaken although it is only seriously done for research purposes: you will see how small some shells can be from the image and only the tiny hypobranchial gland yields dye. In the mid nineteenth century, no-one knew the full process, which is why I found Robert Browning’s poem Popularity (1850s) so interesting when I came across it this week.  Crucially within it is a several-verse reference to Tyrian Purple and shellfish dye. As I couldn’t fathom what the whole poem was about, this reference was a puzzle. I sought out the RPA (Resident Poetry Advisor) who explained it to me, along with some literary context which includes Browning’s life and work, a knowledge of Keats and the poets that imitated him. Popularity is dense and complicated.

Popularity: As I now understand it, and in simple terms, the poem is about inspiration and skill. Browning asks himself about genius, as he did when studying, say, the paintings of Old Masters.  What is genius? Where does it come from? When some ‘poets’ recognised genius in others, as in the work of Keats, they picked up superficial, outward facets of the verse and imitated them. They basked in their hollow cleverness. Browning describes the humbleness of the shells, or conches (‘Mere conchs!’) and celebrates the ‘cunning’ of those who learned how to refine this costliest ‘dye of dyes‘. What’s the humble origin of Keats’ unique genius, he wonders wittily in his last line:

What porridge had John Keats?

Contemporary knowledge in the 1850s

Considering the knowledge that Browning appears to have of dye preparation:

Till cunning come to pound and squeeze
And clarify,—refine to proof
The liquor filtered by degrees

it could be that he knew a little more about the process than was available through classic texts. Henri de Lucaze Duthiers was working on shellfish dyes in the 1850s, but not for dyeing. He was demonstrating the potential to use the molluscs for a photographic printing process. I don’t see enough evidence to draw any conclusions about what Browning knew, but it’s been fun speculating, and a reminder of the magic we dyers experience liberating colour from simple, natural materials.

To read the whole poem Popularity, you can go here, but two key verses are below.


Who has not heard how Tyrian shells
Enclosed the blue, that dye of dyes
Whereof one drop worked miracles,
And coloured like Astarte’s eyes
Raw silk the merchant sells?


Mere conchs! not fit for warp or woof!
Till cunning come to pound and squeeze
And clarify,—refine to proof
The liquor filtered by degrees,
While the world stands aloof.


NOTE: *Dyeing, as opposed to smearing. Traditional use of shellfish to colour threads and cloth, such as in Oaxaca, Mexico, is not true vat dyeing, but more akin to  surface smearing.

Links about my research, on this blog

Overview  Dyes, History and a chilly trip to Yorkshire

About orchil: Talking Orchil

My research information: Historical Dye studies


Cooksey, Chris (2013) Tyrian Purple: the first four thousand years, Science Progress, 96(2), p 171 – 186

Jordan, Maria (2012) Recreating the life of a tapestry: Fading dyes and the impact on the tapestry image available online from The Institute of Conservation here

Chris Cooksey’s Tyrian Purple Bibliography

Wikipedia on Tyrian Purple


With thanks to Dr Maurizio Aceto for some input on dates, Nigel Phillips for giving me the Nucella lapillus shells in Somerset last summer, and especially to the RPA.