The Alchemy of Paint E-Book

Spike Bucklow

• Herausgeber: Marion Boyars
• Kategorie: Geisteswissenschaft
• Sprache: Englisch
• Veröffentlichungsjahr: 2009

Beschreibung

Spike Bucklow sets out to unravel the myths behind the pigments, like dragonsblood, which is said to be a mixture of elephant and dragon blood. Examining both the medieval palette and the often cloak-and-dagger science that created it, he uncovers the secret recipes behind the luxurious colours we are familiar with today. Driven by an overriding passion for art, Spike Bucklow's aim is to restore value to colour.

Leseprobe

THE ALCHEMY OF PAINT

Art, Science and Secrets from the Middle Ages

by Spike Bucklow

festina lente

‘THE MOST RENOWNED PAINTERS used only four colours to paint their works…Even so, each picture sold for the price of a whole town. Now, when purple finds its way onto the walls of rooms and when India furnishes the mud of her rivers and the gore of her snakes and elephants, there is no first-rate painting…people nowadays value materials above genius.’

Pliny the Elder, Natural History, (XXXV, 50) - 1st century AD

Why collect the mud of India’s rivers?

What is the gore of her snakes and elephants worth?

And what is the value of purple?

CONTENTS

Title Page

Dedication

Epigraph

Acknowledgements

Foreword

Preface

Chapter One Colour: Dyes, Pigments and Metals

Chapter Two Ultramarine: From over the Seas

Chapter Three Vermilion: Towards the Philosophers’ Stone

Chapter Four Metallic Blues: The Powers of the Planets

Chapter Five Dragonsblood: The Fruit of Mortal Combat

Chapter Six Gold: The Riches of the Unknown

Chapter Seven Colour: The Other Side

Chapter Eight Vermilion: The Sublime, Crystallised

Chapter Nine Gold: The Love that Conquers Death

Chapter Ten The Science of Colour: Epilogue

Notes on the text

Bibliography

Glossary

Index

About the Author

Copyright

ACKNOWLEDGEMENTS

This book developed from lectures given at the Hamilton Kerr Institute, Fitzwilliam Museum and University of Cambridge International Summer Schools. Thanks are due to Sarah Ormrod and all her students (especially the class of ’08 – Maria José Arjona – Peris, Leslie Barr, Karen Crane, Moira Feinsilver, Iris Hoogendoorn, Alexandra Karagianni and Estella Rizzin). Thanks are also due to Institute students and interns, too numerous to mention by name. Some of the ideas were first aired in Zeitschrift für Kunsttechnologie und Konservierung, ’99, ’00 and ’01. The idea for a book came from Tiana Dougherty, its final shape owes much to Clare Osdene Shapiro, Catheryn Kilgarriff, Rebecca Gillieron and especially Kit Maude.

I would like to thank the following for their encouragement, support and patience; Juan Acevedo, Linton Bocock and the Mold Room, Hilary Bourdillon, Ruth Hart Brown, Sarah Burwood, Jo Dillon, Rupert Featherstone, Alison Fell, Eike Friedrich, Marianne Fitzgerald-Klein, Kate Fletcher, Nicholas Friend, Helen Glanville, Christopher de Hamel, Andrea Kirkham, Andria Laws, Maria Madrid, Ian McClure, M.A. Michael, Doug Mollard, David Oldfield, Stella Panayotova, Patricia Salazar, Pamela Smith, Wolfgang Smith, Francis Sword, Ferdinand Werner, Mandy Worrall, Renate Woudhuysen and Lucy Wrapson. Most of all, I wish to thank my family.

Dedicated to the memory of Dr Martin Lings (1909–2005)

FOREWORD BY DR PAMELA TUDOR-CRAIG, LADY WEDGWOOD

This is a dazzling book. If the mysteries of alchemy appeal to you, it is a necessity. If you use paints, you must struggle with it, even to the point of considering some of the recipes. Improbable though many of them are, Bucklow has tried them and testifies that they can work. The science behind them is unlike ours. He reckons most of it is five thousand years old. He admits that the distinction between it and magic is foggy, but this science is convergent, unifying, and magic scatters, disperses. This science is based on the properties of the four elements, which can intermingle if they have ‘concordant’ qualities, but not if they present ‘contrasting’ qualities to one another. In these pages there is a litany of precious pigments and how medieval artists refined them. He goes from Tyrian purple, extracted from a gland in Murex snails, and scarlet from pregnant beetles clinging to oak trees, to ultramarine from lapis lazuli, through vermilion, to dragonsblood, which does not issue from a battle to the death between a dragon and an elephant, but is a mastic. On p.173 we come to gold, and from that point the narrative becomes totally compelling. Bucklow argues cogently that the value we still attach to gold is based not on rarity or even beauty, but on the property, appreciated in the centuries of faiths, of indestructibility. It cannot be destroyed by fire or by liquids. It has been endlessly recycled. It is the nearest thing on this earth to immortality.

This takes us to what the author calls ‘The Other Side’, the inner meaning of this alternative science. Now he begins again with the Virgin’s robe, of pure white wool dyed Tyrian purple, which was taken in the 7th century to Hagia Sophia, and its symbolic significance. This purple is originally pale yellow, which darkens to purple with exposure to the sun, but does not subsequently fade in sunlight. So the robe is richly symbolic. From there he explores the mythology around vermilion, returning again to the supremacy of gold. Unlike other substances essential to pigments, gold has been found almost everywhere (in Wales, for instance, before the Romans). At this moment in a climate of dwindling values, gold has once more asserted its supremacy. Perhaps our financiers should read this book. What about a new gold standard?

Along the extraordinary path which Spike Bucklow has carved through the intricacies of alchemy he has encountered the mystic Walter Hilton, and the medieval philosopher and scientist Albertus Magnus, whose many tomes included a lapidary. He has drawn upon Dante and Shakespeare, Achilles, Persephone and Pluto, Plato and Aristotle. He pays tribute to the prodigious Islamic contribution. The late 13th century lapidary of Alphonso X of Spain contained a recipe for making golden stained glass. Golden stained glass immediately became the vogue right across Europe. Rich mines for silver were exploited in the Harz mountains, in the 10th century and in the 11th and 12th centuries in Austria and the Tirol. By the 13th century. European silver was mostly exhausted. So now I understand why the greatest Bibles of the 10th and 11th centuries used so much silver. How lovely they must have looked, but now alas…

You will find here the explanation for the globes divided by a T-cross which are almost ubiquitous in the hand of a Medieval Christ in Majesty: the vertical bar is the Mediterranean separating Europe from Africa, with Europe to left. The horizontal bar, formed by the Nile and the Don, divides Africa and Europe from Asia. The partitions represent the apportioning of the world between Noah’s three sons.

This book is a treasure house of knowledge, some of it originally deliberately obscured, like the secrets of the Masons. I am convinced the knowledge was passed from master to pupil through apprenticeship, and that it would have been almost impossible to follow the recipes from a book until you had already learnt them – through practical experience and from a practitioner. The almost bewildering range of reference so ably handled here reflects the Medieval world view, which saw all knowledge as ultimately one.

‘Every scribe who is instructed into the kingdom of heaven is like a householder who brings out of his storeroom things both new and old.’ – Matthew 13:52. Spike Bucklow is such a scribe.

Schematic of the Hereford mappa mundi (c.1300) with selected features of the Old World.

KEY

IIGriffinIVAfghanistanVIParadiseVIIIElephantXTower of BabelXIIJerusalemXIVBasiliskXVIGold-digging AntsXVIIIPillars of HerculesXXHerefordXXIIRomeXXIVNorth Pole

PREFACE

As a scientist working in the art world, I spend time balancing value systems that are sometimes in competition. Of course, both science and art have more than one value – some scientific endeavours are valued for their contribution to knowledge, and others, for their utility. Art has innumerable values. For example, as a conservation scientist, when dealing with the physical nature of works of art, I try and reconcile art’s historical and aesthetic values when the venerable signs of age may impede the object’s intended function as a work of beauty.

Whatever values may reside in science or art separately, science’s values are mainly material and art’s are not – or its most interesting aspects are not material. The value of Van Gogh’s Sunflowers, for instance, has almost nothing to do with the number of grams of canvas, oil and pigments it contains. If it did, then a tiny chip from one edge of the painting might pay-off my mortgage. Yet, separated from the whole, a tiny fragment of a painting has quite limited value. (Although microscopic samples can tell us about the artists’ materials and methods and, as such, have helped inform this book.) Much of a painting’s value lies in what it is not. A landscape, for example, is not really a landscape – it’s canvas, oil and pigment.

For the past few centuries, much of Western art’s appeal is the fact that it plays with illusions. We know that a landscape or a portrait is really only a pattern of pigments, but we happily enter into the game that it’s a place or a person. In the middle ages, art’s willingly-engaged-in illusion was also seen in nature. Then, art and the natural world studied by science both had something illusory and immaterial about them.

This book explores colour in art and nature. It looks at what artists’ materials meant to medieval painters and patrons and it attempts to rediscover some of colour’s meanings by looking at the science behind the art of the middle ages.

Today, the science that produces colour is dominated by men in white coats. It is completely divorced from the artists’ studio and from our day-to-day lives. But the science this book explores was an integral part of every artists’ life and work and it was widely known outside the studio. The chemistry explored here has aspects that might seem similar to activities undertaken in modern laboratories. Yet it also has a much more important aspect; one that is a lot closer to the chemistry that exists between lovers.

We might recognise the presence of such chemistry in our own lives, but we are usually too close to see exactly how it works. Clarity often comes when we put some distance between ourselves and the subject in question. We can learn much about emotional, spiritual and philosophical chemistries from the traditional recipes that describe the preparation of colours, some of which survive from before the time of Christ. The earliest examples are not records of innovations – they commit to writing what had already existed in an oral tradition. They also seem to repeat documents that are now lost. The authors of some recipes misleadingly attributed their writings to historical figures such as Plato or Aristotle. Other recipes are ascribed to possibly legendary figures like Hermes. There are even recipes describing technologies that were said to thrive before the Flood, knowledge of which was rescued in Noah’s Ark.

The origin of these craft traditions is part of the now-lost ‘wisdom of the ancients’, the wisdom of Shakespeare’s Duke who, exiled in the Forest of Arden,

‘Finds tongues in trees, books in running brooks,

Sermons in stones, and good in everything.’1

This book introduces dyes, pigments and metals as items of importance outside the artists’ workshop and then explores a few from the point of view of the artists who used them, starting with the story of a stone from beyond the centre of the earth. It looks at a chemical marriage that echoes a mystic marriage, stories about the influence of heaven, mortal combats and the quest for gold. It will explain how colour was ‘read’ in the middle ages, returning to materials to look at the hidden meaning of the artists’ version of the Philosophers’ Stone. Following the wisdom of the ancients, the penultimate chapter explores the potentially life-changing secret that artists and alchemists saw hidden in gold.

In writing this book I have drawn upon the writings of artists as well as the works of philosophers and scientists. But it is not a history of art, of philosophy or of science. In fact – for those who wish to experience colour with fresh eyes – it is not even history, although it draws upon historic examples. It is an exploration of commonly held and influential beliefs, as revealed by dyes, pigments and metals (not to mention a few children’s games, fairy-tales and proverbs).2 By listening to ‘tongues in trees’ and by reading ‘sermons in stones’, this book attempts to re-evaluate colour and, along the way, provide a primer or visitor’s guide to the traditional world view.

The traditional world is entirely holistic, but in order to get into it, you have to start somewhere. I start by examining the outside world, the doctrine of signatures, the four elements, form and matter, the four causes, the seven planets and mythology before moving to the inner world. The first half is a cookbook, although it uses ingredients for pictures rather than for meals. The second half looks at how colours can nourish the soul.

The colours in this book are vehicles upon which a much bigger story rides. Treated with sympathy, these colours can carry us to a world that is radically different from the world in which we find ourselves today. But, on the way, some readers may find it strangely familiar.

Notes

1As You Like It, (II, i, 16-17).

2 Shapin, 731-69.

Chapter One

COLOUR: DYES, PIGMENTS AND METALS

Introduction

Colour has been hijacked. Today, orange has been appropriated by a telecoms company and the combination of red and white is associated with a fizzy drink. But there is nothing inherently ‘orange’ about telecommunications and there is nothing inherently ‘red and white’ about soft drinks. In fact, other telecoms companies manage to trade under different livery, and another practically interchangeable fizzy drink has a comparable share of the market despite different coloured packaging.

Of course, in the bigger picture, the life of telecoms companies and fizzy drinks is limited. So, at some time in the not too distant future, the associations between these particular colours and products will have been forgotten or, if remembered, they will be considered quaint. A few cultural historians may even ponder over them. Yet, the reason that these colour associations exist is simple – they are created by a very small number of people in an attempt to persuade a very large number of people to buy one particular product rather than another that is more-or-less equivalent. If – by luck or by judgment – they are successful, then the colour association endures until the product is re-branded or falls from favour.

As a result, we now expect to be able choose a particular coloured item from a range of otherwise identical items. We can buy cars, for example, in an astonishing array of colours. The multitude of coloured cars may brighten-up the urban landscape, but each of them will inevitably end up as scrap whilst the concrete and tarmac roads they require spread relentlessly in monotonous shades of grey.

However, colour can only be used in an arbitrary fashion when existing colour associations are absent or weak. Are there relatively few green cars, for example, because green is still an ‘unlucky’ colour? And is green unlucky because a 19th century green was made from arsenic, poisoning thousands, allegedly including Napoleon? Such questions remain open and colour associations keep changing; green, for example, now also signifies ‘ecological’. The associations that exist for particular colours are too fluid and often too personal to have a recognised place in the rigid and impersonal modern world, where they are instead dismissed as subjective or unreliable if not outright frivolous. Unless it helps shift a product or has a tangible purpose, controlling traffic for example, colour is treated as if it really doesn’t matter.

Yet at a personal level, we know that colour does matter. We choose colours for our homes carefully and we spend time, effort and a significant amount of money decorating and re-decorating. Our sensitivity to the subtlest nuances of colour is demonstrated by the fantastic range of cosmetics that are available, from lipsticks, through skin creams, hair dyes and much more. Some of us choose colours with confidence and others, who might be less sure about their judgement, employ willing professionals to help select the appropriate shade with which to decorate their homes or themselves.

In spite of our investment of time and money, the way we treat colours in the modern world collectively devalues our whole experience of them. Next year’s fashions will be different, so if the colour of something has any significance whatsoever, then its meaning is fleeting. Colour has been turned into an ephemeral commodity. And having been encouraged to take the colour of man-made things as merely conventional or an interchangeable add-on, it is very hard for us to imagine a world where colour had significance in its own right.

We might know little or nothing about the chemicals that colour our cars, clothes, cosmetics or even our food, but this state of affairs is quite recent. Consumers in the middle ages knew where their colours came from and what they meant. Whether of animal, vegetable, mineral or artificial origin, colours had stories to tell that touched all members of society. For millennia, colour was not just another variation in manufactured products. It was profoundly meaningful. Each colour had numerous values associated with it, and those values were coherent, stable and widely known.

Colour is a profoundly beautiful part of the sensuous world but, over the last three hundred years, its deeper significance has gradually been forgotten and our world has become poorer as a result. It is possible to reclaim the richness that colour once possessed, but this requires quite a radical change of outlook. Rescuing colour from the limbo of arbitrary associations and subjective status involves treating it as a meaningful and objective phenomenon. After all, we can’t reasonably expect colour to reveal its full glory to us if we don’t pay it some respect. It is not difficult to rediscover colour’s forgotten dimensions – all we need to do is recognise the ways that we habitually treat colour and then make some choices.

First, there is a tendency to treat colours as if they are interchangeable. We behave as if colour is not necessarily connected to something’s function. In theory, of course, we still know that the colour of fruit tells us about its ripeness, but we don’t see many green oranges in supermarkets. In practice, we know that some citrus fruits are orange and some telecoms companies are represented by the colour orange, but we don’t expect there to be any real connections between the two. We accept that no really important connections are likely to exist between things based on their sharing the same colour. (Of course, connections based on colours are real and important for the fashion industry or for football fans, but they have well-defined sell-by-dates or are little more than local membership signs.)

Second, we have a habit of treating colour as if it is instantly accessible. Colour would not work in fashion or in football if we could not instantly tell that someone was wearing this or last season’s colours or was supporting our team or the opposition. And branding with colours would not work if we had to spend time studying products in supermarkets. We expect that whatever colour has to offer us is there for the taking, with little or no effort.

A fragmented and instantly accessible phenomenon, with arbitrary associations and a subjective status, can only have limited cultural impact. But other cultures treat colour differently, and one of the most accessible cultures to have a different attitude to the subject is not many miles away – it is the medieval world, the culture that sowed the seeds of our modern sensibilities. C.S. Lewis’ The Discarded Image showed how the medieval model of the world shaped European literature and this book explores the same model to re-establish a lost relationship with colour. Each successive chapter tries to get deeper and deeper into the mind set of pre-modern or medieval Europe. Each chapter is devoted to just one colour, giving the respect it deserves and acknowledging its significance to life in the traditional world.

Most traces of the historic use of colour have gone, but the obvious survivors are the great paintings that helped shape the way we see the world today. For the people who commissioned and who created those paintings, dyes, pigments and metals were materials with their own intrinsic values as well as sources of colour. What a colour meant inside a painting depended upon what it meant outside the painting. The following chapters will look at a midnight blue called ultramarine, an opaque red called vermilion, a multitude of colours made from metals, a transparent red called dragonsblood and finally, gold. Towards the end, I will revisit vermilion and gold to see how they throw light on the way we see ourselves and the way we interact with the world. This chapter sets the scene, showing how sources of colour were valued as objects of trade, as the focus of scientific enquiry, and as spiritual supports.

Painters undoubtedly valued colours. But they were also prescribed by physicians and taken by patients. They paid the rent for farmers and fishermen, paid taxes for entire nations and were the spoils of war. First hand knowledge of dyes, pigments and metals was not restricted to painters but the technical manuals they wrote provide part of the context that we need for a deeper understanding of colour. Theophilus, a Benedictine monk and artist who lived in the 12th century, wrote one of these manuals. In it, he claimed

‘…you will find whatever kinds of the different pigments Byzantium possesses and their mixtures; whatever Russia has learned in the working of enamels and variegation with neillo; whatever Arab lands adorn with repoussé or casting or openwork; whatever Italy applies to a variety of vessels in gold or by the carving of gems and ivories; whatever France loves in the costly variegation of windows; and whatever Germany applauds in the fine working of gold, silver, copper, and iron, and in wood and precious stones.’1

Origins

One might be attracted to colours with exotic origins, but they could be found everywhere. Theophilus (a German) valued the skills and materials that came from Byzantium, Russia and Arabia, yet he also advised the artist not to ‘disparage any costly or useful thing just because your native soil has spontaneously and unexpectedly produced it for you.’2

An Italian painter walking around Siena in search of a golden pigment would find it underfoot. Medieval Siena’s streets were not exactly paved with gold, but they were made from a golden coloured earth that gives us the colour we now call ‘raw sienna’. Such colours were not restricted to Siena and English painters also had access to equally good local earths. Even today, Gloucestershire’s ‘Freeminers’ still exercise their ancient birthright to make pigments from the golden, red and purple earths of Clearwell Caves in the Royal Forest of Dean.

Black was even easier to find. In his manual, the 14th century painter Cennino Cennini recommended charring ‘the second joints and wings of fowls or of a capon…Just as you find them under the dining-table…the thigh bone of a gelded lamb is good too…’3

But, in addition to using discarded bones, black pigments could also be made from ivory. Bone black and ivory black look identical when used in paint or ink so the same colour in different objects could just as likely have a rather prosaic or an extremely exotic origin. It may have been discarded from the artists’ dining-table and saved from the dog. Or it may have been shaved from an imported elephant’s tusk, recycled from a precious carving. One couldn’t tell just by looking.

When artists’ materials were rare or costly, they tended to acquire exotic or fantastical origins. For example, Tyrian purple was much more important than the dirt of Siena’s streets; legend says that it was discovered by Hercules when wooing the nymph Tyros and playing with his dog on the beach. His dog chewed some seashells and stained its nose purple. Tyros admired the colour, persuaded Hercules to dye a garment for her, and an industry was born.4

True Tyrian purple was extracted from a gland found in Murex snails. For millennia, these were caught in vast numbers around the Eastern Mediterranean together with other related snails.5 They are carnivorous and can bore though shells to inject their prey with incapacitating muscle-relaxing toxins. The traditional method of catching snails took advantage of their feeding habits.6 According to the 1st century natural philosopher, Pliny the Elder, baskets baited with meat were thrown into the sea and, when retrieved, ‘the purples hang suspended because of their greed and are lifted out of the water.’7

Another unlikely animal was a source for scarlet which was extracted from scale insects.8 The most important kind was ‘kermes’, named after the Persian for ‘worm’. The pregnant females were collected when their egg-sacs were so swollen that they could not move and the immobilised insects looked like berries on oak trees. Some thought that the worms were created inside the ‘berries’ as they rotted and the distinctive red liquid was assumed to be their blood.9

The creation of worms inside rotten oak berries was in keeping with the scientific theory that maggots were created by putrefaction. After all, flies emerged from carrion and – according to the riddle Sampson set the Philistines – bees came from dead lions.10 So, honey’s sweetness came from the decay of the King of the beasts and scarlet’s splendour came from the decay of the King of the trees. Women gathered kermes from oak trees all around the Mediterranean.1112

‘Kirmiz’, the colour Armenian red, was extracted from a different insect that lived on grasses around the foot of Mount Ararat.13 These were collected by gently lifting the grass, plucking the immobilised pregnant insects off the roots, and replanting ready for next year’s crop. Cochineal, a third important source of insect red, was cultivated commercially in Poland, Prussia, Saxony, Lithuania and the Ukraine. The cochineal harvest started on the fifth hour (between eleven o’clock and noon) of St John the Baptist’s feast day, accompanied by religious ceremonies.14

The scale insects of the Mediterranean, Armenia and swathes of Northern Europe are no longer disturbed by such harvests. In the 16th century, they were largely replaced as sources of reds by insects from the New World.15 Even today, these poor creatures still contribute their colour to our lipsticks and foodstuffs (their ‘blood’ does not have the unfortunate side effects of modern synthetic red food-colouring).

Tyrian purple and the insect reds had obvious bright colours. However another artists’ material, alum, was very important even though it had no colour at all. Alum comes from a very different earth than the coloured kind found around Siena and elsewhere. Some ancient sources for alum were located around the Bay of Naples where crystals grew in the curative waters of natural spas,16 but the majority came from Turkey, so supplies depended upon trade between Christendom and the sphere of Islam.17 Because of the interference caused by the various crusades and other wars, this was not always easy. European sources were required.

Alum prospectors needed to know why the nature of earths varied from one location to another – some science was needed to guide their search. Just as medieval scientists knew the feeding habits of snails at the bottom of the sea and the breeding habits of insects underground they also knew why there were different kinds of earth across the face of the planet. They theorised that the various types of earth were created according to how different constellations of stars passed over given places at given times. According to Albertus Magnus, heaven acts upon earth, and, because earth is the ‘centre of the whole heavenly sphere; and the power of the rays is strongest where they converge…therefore Earth is productive of many wonderful things.’18

As the stars and planets rise in the east, their influence on earth is first felt there. Pythagoras said, ‘that which has precedence is more honourable than that which is consequent in time. As for instance…the east is more honourable than the west…’19 Eastern precedence shows in the potency of stones that were produced there and Albertus Magnus claimed that powerful stones came from India and Egypt because ‘the power of the planets is most effective in those places…’20

Alum is a powerful stone. So it would have come as no surprise to classical and medieval geologists that Europe’s best alum should come from Turkey, which lies towards the east. Later, alum-bearing earths were found in Italy and later still, in England, on the east coast of Yorkshire. Local conditions must have accounted for these smaller sources. The English source of alum, Jurassic shale, was described in the 17th century:

‘In it are Snake-stones. The people have a Tradition that the country thereabouts was much annoyed by Snakes which, by the Prayers of St Hilda, were turned into Stones, and no Snake hath since been in those parts.’21

Alum-bearing snake-stones still feature on Whitby’s coat of arms22 and another type of snake-stone will be considered in chapter five. But artists couldn’t just put these materials straight into their painting – each pigment had its own special way of being prepared before it could be used.

Preparation

Preparation contributed to the appreciation of finished objects because, in the traditional world, products and the processes that made them were intimately linked. This is borne out in literature: in the Iliad – just at the fateful moment when Pandarus decides to break the truce between the Achaeans and Trojans – Homer interrupts the dramatic flow of the narrative to describe the materials and manufacture of Pandarus’ bow and arrow. (The bow was made from the horn of an ibex that Pandarus had killed, polished by a craftsman, tipped with gold and strung with ox-gut. His arrow was feathered, notched and tipped with an iron point.)23

Like bows and arrows, paintings were valued because of the materials that they contained. But they were also valued because of the mysterious ways craftsmen could convert raw materials into something with fateful power. Without a craftsman, a small piece of iron, two pieces of gold, an ibex horn, a shaft of wood, some ox-gut and feathers are just that. Individually they are quite unremarkable. Yet after the transformations wrought by a craftsman, and in the hands of Pandarus, those modest materials helped precipitate a tragic epic.

The craftsman’s ability to convert assorted harmless ingredients into useful tools (not just lethal weapons) was widely respected and so too was the artist’s ability to convert raw materials into beautiful colours. For the painter, good reds were quite tricky to prepare from insects in spite of the fact that quite a lot of work had already been put into them even before they arrived in the painter’s studio. The vast majority of insect reds were used for dyeing cloth and painters often extracted the colour from waste cloth by dissolving it in lye. This lye was commonly made by soaking wood-ash in pots full of water.i

The alkali used to extract insect colours from cloth was sufficiently caustic if a fresh egg could float in it.24 (Another test was to see if it could dissolve a feather.25) And artists timed how long the dyed cloth should be left in the alkali by chanting. Cloth was boiled in lye for one or two Pater Nosters, two or three Misereres, or for three Ave Marias according to different recipes26. The discovery of microscopic remains of cloth in paint, for example in Titian’s Venus and Adonis,27 confirms that artists recycled textiles to make what they called ‘lake’ colours.ii

Insect reds were used to dye high-status textiles like ecclesiastical, regal and military robes as well as less obvious things, such as the manes and tails of Turkish horses.30 But if you used these dyes alone, then the colour would wash out the first time the cloth or the horse got wet. Similarly, you could not paint with the dyestuff alone. The colour had to be used together with another material, a ‘mordant’, which locked the colour to the cloth or in the painting. The most commonly used mordant was alum.

According to the Philosophical Transactions of the Royal Society of London of 1678, alum was usually made by burning a particular stone continuously for between nine and twelve months. Depending upon the ‘illness of the Mineral’, the burnt stone was soaked in lye made from the ash of burnt seaweed or stale urine (the best from ‘poor labouring people who drink little strong drink’) which worked like ‘yeast put to beer’. The liquor was drained from the stone and then boiled-off to leave the alum.3132 Although published in the 17th century, the process was nothing new, in fact, any alum maker from the preceding two thousand years would have recognized it.33

Urine was not only used to make alum, it was also used in the dyeing process. In ancient Pompeii, public toilets delivered the citizen’s urine direct to the dye-works. (The use of urine continues in the modern chemical industry. Today, sewage plants still supply some factories. The names of plastics, like ‘urea formaldehyde’ and ‘polyurethane’ betray the use of urine as a possible ingredient and some cheap plastics have a distinct smell of stale urine.) This technical detail probably accounts for Strabo’s observation that Tyre – the centre of production for Tyrian purple – was an unpleasant place to live. The stench of crushed snails and stale urine must have hung, miasma-like, over the town for half the year.34

Stale urine was sometimes known as ‘chamber lye’ to distinguish it from alkalis made from wood-ash, artists sometimes seem quite precise about the type of urine they wanted. A collection of recipes written in the 3rd century specifies urine from goats, sheep, camels, she-asses and ‘an uncorrupted youth’.35 In a 12th century recipe, Theophilus specified urine from a red-haired boy.36 (The following chapter explores the ‘doctrine of signatures’ which suggested that red-haired people had ‘fiery’ temperaments that were reflected in the particularly ‘burning’ nature of their urine.)

The preparation of another kind of earth was more straightforward – no urine, of any type, was required. The yellow earth from the streets of Siena just needed to be dug-up, ground-up and washed in water to be ready for the palette. But if artists wanted to change the colour of their local earth, they could. Yellows especially could be changed into oranges and reds. Cave paintings in the French Pyrenees, for example, show that Palaeolithic artists transformed their pigments over ten thousand years ago.37 The earliest record of making red colours from yellow earths is in an Assyrian cuneiform tablet of 1,700 BC3839 and numerous authors mention heating yellow ‘raw sienna’ to make the red that is now called ‘burnt sienna’. Just as red hair is an indication of a person’s fiery temperament so the red colour of burnt sienna indicates the effects of fire on stone. Theophrastus said that yellow earth was heated in a fire until it became ‘like glowing charcoal’.40

The artists’ earth-roasting fire modestly mimicked natural fires caused by lightning-strikes and their production of a pigment that imitated the glowing charcoal used in its creation suggests a close observation of nature. The relationship between artists’ production of colour and their observation of the natural world is further demonstrated by the profound knowledge of marine snails and subterranean insects.

Sixty insects were needed to make a gram of dye41 and dyeing could take place anywhere and at any time because the insects were dried immediately and could be stored or transported. On the other hand, eight thousand snails were needed to make a gram of Tyrian purple and it had to be extracted from live snails so dyeing took place along the coast, close to where the snails were caught. Processing was seasonal – Aristotle said that they were ‘not caught in the dog-days’42 the height of summer, when the dog-star, Sirius, spent more of its time with the Sun.43 Once caught, they had to be kept alive until hundreds of thousands could be processed at a time, crushing smaller snails whole and removing glands from larger ones.44 Pliny claimed that, when caught, snails could live as much as seven weeks ‘on their own slime’45 and Aristotle observed that, if hungry, they would bore through the shells of their own kind.46 In fact, archaeologists have found shells discarded from the dye industry with holes in them.47 Evidently, snails were sometimes not fed enough whilst awaiting their fate so they resorted to cannibalism.

Economic use

Colours were so widely used that they had great economic importance. Clues about Tyrian purple’s economic significance, for example, come from the number of recipes for fake purples using ingredients as diverse as hellibore, pomegranate blossom, gall-nut, hyacinth, mulberry, grapejuice, henbane, lupine and heliotrope.48 The Talmud even records chemical tests for detecting the fraudulent use of ritual dyes.4950

Today we are used to the regulation of manufactured goods, but – in the history of mankind – such regulation is relatively new. Commercial restrictions on the manufacture of Tyrian purple were formally introduced as late as the 4th century. However, when regulations were eventually introduced, they were strict. Imperial Edicts made the unauthorised production of purple a capital offence.51 In the 5th century, with production of purple already forbidden, the private possession of purple silk was made illegal. Nonetheless, a black market still existed and possibly in response to this, in the 6th century, trade in silk became an Imperial Byzantine monopoly.52 A 10th century text listed detailed regulations relating to silks in general and purple silk in particular. Along with trade restrictions, there were technical restrictions, for example, the weaving together of different purples was banned because Tyrian purple was permanent, whilst other dyes faded.53

From the 7th to the 10th centuries, trade in ‘forbidden silk’ was fiercely protected and dyeing was a jealously guarded secret.54 But with the fall of Byzantium, purple’s secrets were lost, only to be rediscovered in the late 17th century by William Cole of Bristol who extracted the colour from a British whelk.55 This proved, however, to be a mere scientific novelty as it was too expensive to produce commercially.

In the 4th century, the Emperor Diocletian’s Edict of Maximum Prices stated that a pound of purple wool should cost no more than 50,000 denarii, the same as a pound of refined gold. Purple wool was literally worth its weight in gold. Purple silk was even more expensive. In the 4th century, a stonemason’s daily wage was 50 denarii. So a pound of purple wool represented nearly three years’ wages.56 At the other end of the scale, Cleopatra’s wealth is obvious from the description of her barge,

‘Purple the sails, and so perfumed that

The winds were love-sick with them…’57

But even though Tyrian purple was extraordinarily expensive, it was the scarcity of the snail and the Imperial monopolies that really limited its use. In fact, red grain colours could be just as expensive.

Today, ‘scarlet’ describes a colour, but it was originally a type of cloth.58 Henry VI’s wardrobe accounts for 1438–9, show that his cheapest scarlet was £14.2s.6d. and that scarlets could fetch up to twice that price.59 By the 15th century, a stonemason’s daily wage was sixpence. So, coincidentally, Henry’s cheapest scarlet was again nearly three years’ full wages. In the 15th century, a mid-priced scarlet cost more than two thousand kilos of cheese or one thousand litres of wine.60 This expense accounts for the custom of giving important visitors the ‘red carpet treatment’.

Flemish scarlet cloths were made of the finest English wools. At the end of the 15th century, wool cost between £15 and £28 per sack. (About one shilling, or two days wages for our stone mason, per pound of wool.) The cost of the dye accounted for most of the total cost of a scarlet.61 As dried insects looked like grains they were named as such, and these ‘grains’ were important items of trade. For example, in eastern Europe in the 12th and 13th centuries, dried cochineal insects were used to pay tithes to the Church.62 At the beginning of the 14th century, Edward I imposed taxes on imported cloth determined by dye content – ‘whole grain, part grain and no grain’.63 But he was not the first monarch to show an interest in the control of red insects – two-and-a-half thousand years earlier, Tiglath-pilese I of Assyria introduced oak trees from the Mediterranean to act as hosts for kermes to supplement his Armenian red supplies.64 In the 1st century AD, Pliny recorded that a red grain called scolecium or ‘little worm’ was harvested in Spain to pay half the annual tribute it owed to Rome.65

Expensive as they were, the economic importance of insect reds and other dyes was rivalled by that of the alum required to permanently fix them to cloth. The acquisition and preparation of Turkish alum were politically charged affairs because numerous crusades and the collapse of Byzantium made supplies erratic. So news of the discovery, in 1458, of alum-bearing rocks around Volterra in Italy, was met with great celebration. Expertise and finance were sought from nearby Florence and Siena and a partnership was formed to exploit the source. Friction quickly developed and precipitated a war between the city-states. Eventually, Volterra was annexed by Florence.66

Three years later, in 1461, Giovanni de Castro, the son of a lawyer from Padua, discovered a much bigger deposit of alum-bearing rocks at Tolfa. De Castro had worked as textile agent in Constantinople before the fall of Byzantium and had seen Turkish alum works. Back home in Italy, he was ‘struck by strangeness of the herbage and of white stones’ which he tasted and, upon finding them ‘saltish,’67 started experimenting. Experts tested his results and they eventually greeted his success with ‘tears of joy…kneeling down three times [they] worshipped God and praised His kindness in conferring such a gift’.68

As the alum-bearing rocks had been found on Papal territory, finance for establishing an alum works was sought from Pope Pius II. This was not difficult. The significance of the discovery was obvious. De Castro recognised that the alum had strategic potential, simultaneously weakening the Turks and strengthening the Pope.

‘I announce to you a victory over the Turk. He draws yearly from the Christians above 300,000 gold pieces for the alum with which we dye our wool…This mineral will give you the sinews of war.’69

In the spring of 1463, within two years of the discovery, there were four mines in Tolfa, employing 8,000 workers and contracted to provide 1,500 tons of alum a year to the Pope. The trade was so important that the Pope’s Maundy Thursday address of 1465 listed in extraordinary detail the punishments that awaited those ‘perfidious Christians’ who continued to buy Turkish alum or assist ‘the Infidel’.70

The Pope had established a cartel to control the market and, in 1466, the Medici became bankers and agents for the alum trade. Meanwhile, the Pope was negotiating with the King of Naples to combine trade in the Tolfa alum with the smaller quantities coming from the re-opened ancient sources in the south. Agreement was reached in 1470 and the Medici acted as agents for alum from both Rome and Naples. In 1471, eight years after opening the mines, the income from Tolfa was 140,000 ducats.71 Tolfa alum ships flew the Papal ensign, were protected by naval vessels, and the importation of alum from Turkey was prohibited. Alum revenues provided economic support for those attempting to subvert Turkish rule and pensions for refugees. But they never funded the hoped-for crusade.72

Whilst the political outcome may not have been what the Pope wanted, trade was so brisk that the Medici bank in Bruges had to moderate the flow of alum and occasionally even suspend sales in an attempt to maintain a good price.73 But the monopoly grew harder and harder to police and, in 1504, Pope Julius II learned that Turkish alum was being traded openly in Venice. On another front, the Pope fought a losing battle when he tried to intervene with the plans of an English skipper, Nicholas Waring. Master of the ship Sovereign, he set to sea to buy Turkish alum after being frustrated by an inordinate delay in loading the Tolfa variety. Julius II wrote repeatedly to Henry VII demanding adherence to the monopoly to little avail. Waring successfully unloaded his cargo at Southampton to only a very token reprimand from his King.74

England imported alum for centuries and, by the mid-16th century, serious efforts were made to find local sources. Over the next hundred years, patents and monopolies were issued, finance was raised, foreign experts were employed, mines were established (in Ireland, Dorset, Lancashire and Yorkshire) with many men meeting bankruptcy and ruin. However, by 1667, enough British alum was being produced for Charles II to forbid its import and issue licenses for the supply of up to 1,200 tons per annum. This limit was set in an attempt to maintain a price of £26 per ton which would give the Crown an annual income of around £10,000. All this from alum – a colourless rock whose overwhelming use was to fix insect blood to cloth.75

Medical use

Colours were economically important, but not just because of clothes and paintings. There is much evidence to show a connection between the trade in colours and medicines especially as, throughout the middle ages, most artists’ materials were purchased from the apothecary. (The artist Lucas Cranach even owned an apothecary.) Indeed, the word ‘apothecary’76 comes from a Byzantine word for an import-export house, suggesting the importance of colour and drugs to European foreign trade.77

There were also overlaps between the professional interests of painters and physicians. For example, Sir Theodore Turquet de Mayerne (physician to James I, Charles I and Charles II) was interested in artists’ materials and knew many of the greatest artists of his day. He even wrote a painting manual based upon his discussions with painters like Rubens and Van Dyck.78 At the same time, an Oxford physician, Richard Haydocke, translated an Italian artists’ treatise into English. In his introduction, he explained why he, a doctor, should be interested in technical aspects of painting. ‘The Arte I now deale in, shall be proved, not only a grace to health, but also…a kind of preservative against Death and Mortality.’79

Professional links between medicine and painting were sealed by a spiritual connection; Saint Luke was patron saint of both painters and physicians.

Many animal, vegetable, mineral and artificial products were known to be beneficial to health (some of which are only now being re-discovered). Numerous artists’ materials were included in pharmacopoeia and medical documents routinely mention preparations containing pigments and even gems. There are, for example, records of gems being administered to Lorenzo de Medici. In his case, the gems must have been either ineffective or administered too late, since the remedy was dispensed on his deathbed.80 And, because the patient was rich and powerful, the doctors would have sought excuses for their failure. Sir John Mandeville’s suggestion (that gems lost their virtues when worn by sinful people) would just add insult to injury. A less risky argument could have been based upon the fact that a gem’s powers were lost if it was purchased. Only when received as a gift could one depend upon a stone’s properties.81

Other artists’ materials and gems were known or considered to be poisonous. Indian diamond dust, for example, featured in a plot to murder the goldsmith Benvenuto Cellini. When Cellini was imprisoned in Rome in 1538 he was aware that enemies were plotting to kill him. He discovered that one of his enemies had given a diamond to another goldsmith, Lione, with instructions to grind it up so that the dust could be placed in Cellini’s prison food. However, Lione was poor and powdered a cheaper gem, a beryl, instead of the diamond. In his autobiography, Cellini said that his life was saved by Lione’s deception.82

Of the materials looked at so far, several, including alum, had medicinal properties. Amongst other things, Pliny recorded its use as an anti-perspirant deodorant.83 (And that particular use continues – modern anti-perspirant deodorants contain aluminium chlorohydrate which, as its name suggests, is related to alum.) The red grain colours also had pharmaceutical uses. For example, kermes was used in Neolithic times as a medicine84 and a heart tonic incorporating it was developed in the 9th century by the physician Yahyā Ibn Māsawaih,85 which continued to be taken into the 19th century.86

Today, some classical and medieval theories still contribute to modern medicine and others are recognizable in complimentary medicine. For example, the ethical system underlying modern medicine is essentially the same as that outlined by Hippocrates around four hundred years before Christ and medieval principles can be found in homeopathy.iii

However, many aspects of traditional medicine have been lost in modern Europe. It is these lost aspects that need to be considered in order to regain a fuller appreciation of colour.

The big difference

Today, pigments are not particularly high profile products. No longer is the unauthorised possession of purple cloth a capital offence. No longer does the mining of alum fund wars, nor does it generate colossal fortunes for small cartels. But the possession of other processed natural products, like illegal drugs, still attracts the death penalty in some places. And, like alum, drugs also fund wars and generate colossal fortunes for small cartels. Another material that currently wields economic and political power is crude oil which, like alum, incites and fuels wars and motivates exploration of the farthest reaches of the planet. It also prompts science to find new ways of preparing and refining the raw material. Also like alum, crude oil is exploited to make products as diverse as paints and medicines. Whilst the players have changed, many of the games remain the same.

Yet there is one very big difference between the modern interest in crude oil and the medieval interest in pigments and this has to do with the way in which the image of the self has changed since the middle ages.

The modern world sees man as divided into a body and a mind. The modern experience of the world is filtered through either a body or a mind. We assess how the things in the world – from crude oil to drugs, from pigments to paintings – impact on our bodies and on our minds. We make our living by using our bodies and our minds. We spend our leisure time entertaining our bodies and our minds. We live with a fear of the frailty of our bodies and our minds.

From the modern point of view, the body and mind are quite distinct, although in practice, the boundary is a bit blurred. (For example, the mind’s influence on the body is recognised in the phenomenon of psychosomatic disorders and the body’s influence on the mind is recognised in the use of psychoactive drugs.) Dyes, pigments, metals and gems are coloured materials. So, from the modern perspective, their use in medieval medicine is explicable because, as physical materials, they might have an effect on the body’s physiology. Their use in medieval paintings is explicable because, as perceptible colours, they might have an effect on the mind’s psychology. The traditional physician used kermes to influence the heart when the patient took it by mouth, and the traditional painter used it to influence the soul when the viewer took it in through the eyes.

So it could seem that, in order to understand the medieval attitude to colour, all one has to do is translate the medieval idea of ‘soul’ into the modern idea of ‘mind’. But that would be a mistake. The traditional view of man is not of a being divided into a mind and a body, or even into just a soul and a body. Man is composed of body, soul and spirit. The body and soul are unique to each individual, but the spirit is universal. The traditional view is that every single person is a miniature universe – humans are connected to the earth just as the earth is connected to the heavens. These connections were widely acknowledged; as Jacob Boehme, the 16th century German shoemaker and mystic philosopher said, ‘Man contains within himself as many species as exist on earth’88 and, as Nicholas of Cusa, the 15th century philosopher and Bishop of Brixen said, ‘on earth there are as many species of things as there are stars.’89

The heavens are reflected on earth and both heaven and earth are reflected in humanity. This was the basis of the ‘doctrine of signatures’. For example, in the ‘macrocosm’ (the outside world), the redness of burnt sienna was related to glowing charcoal. Similarly, in the ‘microcosm’ (the individual), red hair was related to a fiery temper and a particularly potent kind of urine.

When a man or woman is considered as a body, a soul and a spirit, then he or she is not completely separate from the outside world. Nor are experiences divided and filtered through a mind or a body. As a composite of body, soul and spirit, the individual is an integral part of the whole of creation. Their body, soul and spirit are connected, to a greater or lesser extent, with all other parts of creation. All the different parts of heaven and earth resonate with different parts of people. For example, from the traditional point of view, the moon resonates with the mind, and this explains why – when the mind is troubled – a stroll in the moonlight helps put things into perspective. Quiet reflection, bathed in the light of the moon, helps clear the mind.

Throughout this book I shall try to be as faithful as possible to the traditional view of the world as experienced by a man or woman made of a body, soul and spirit (living at the very centre of the universe on an earth of four elements, encircled by seven planets).

In this world view, materials have a spiritual side. For example, thanks were offered90 to God when alum-bearing rocks were found at Tolfa in the 1460s and the processing of lake pigments was timed with chanted Pater Nosters, Misereres, or Ave Marias. By contrast today, when more oil is found in Alaska, Nigeria or Uzbekistan, few thanks are offered. And few processes are timed by singing – most are ruled by the clock.

Of course, it might be objected that the Pope did not have purely spiritual motives for giving thanks for alum. It might also be observed that chanting is an eminently practical way of time-keeping. However, even though the Pope’s interest in alum may indeed have been far from spiritual, it would be unreasonable to question the sincerity of all medieval statements. And, just because chanting is practical does not mean that it could not also be spiritually significant. In fact, as shall be demonstrated in later chapters, chanting has magical overtones and the practicality of something can be seen as a direct consequence of its spiritual truth.

Spiritual properties

Whilst so far, only a few exotic and expensive pigments have been considered, evidence that artists valued spiritual properties can come from even the most modest of pigments. Earth pigments are lowly in origin, dug up from the side of the road in Siena or the Royal Forest of Dean. But artists who were not blessed with good local earth colours still had to import these pigments. More or less everybody, however, had access to bones discarded from the dinner table. So, if all one had to do was to gently char bones in the fire as one sat digesting one’s dinner, why bother going to the apothecary to buy ivory black?

Burning the second joint of an old capon made a pigment that effectively cost nothing, but burnt ivory was not free – it was a mid-priced pigment. Burnt capon bone and burnt ivory are indistinguishable to the naked eye so whatever distinguished them (and justified the apothecary’s price) was invisible. It must have been a spiritual property. One of the spiritual properties of burnt ivory is mentioned in a French bestiary. It said that burning ivory, or ‘elephant’s bones’, ‘will drive away all serpents which may be near and have poison in them. No poison can remain there where one burns the bones.’91

There was nothing special about burning bones from the dinner table. But burning fragments of ivory not only drives away venomous snakes, it also repels evil. Evil might also be repelled from any painting or manuscript that contained the burned bones of elephants as a pigment or ink.

I opened this introduction to artists’ materials by quoting Theophilus on what France, Germany, Italy, Byzantium, Russia and Arabia could offer. In addition to this list, the ivory to make an evil-repelling black pigment would have been imported from India. But in an exploration of colours, it is important to remember that trade in dyes, pigments and metals was accompanied by intellectual discourse. Ideas were exchanged as well as materials.

For example, spiritual associations with black ink are also found in the sphere of Islam. Quadi Ahmad gives a recipe for black ink that includes ten local ingredients (hemp-oil soot, gum Arabic, gallnuts, henna, mu, indigo, aftimun, aloe, saffron and rose-water) and four foreign ingredients (Cyprus alum, Indian salt, Egyptian sugar and Tibetan musk).92 It is an extraordinary mixture of exotic and expensive materials just to make a simple black. Making soot from burning hashish would perfume the workshop. Musk and rose-water would perfume the scriptorium. But some of the other ingredients seem to offer few advantages.

A clue to why his ink’s ingredients might have been so rich comes from noting that the Arabic word for ink, midād, is related to the word for divine substance or matter, mādda. The connection between the words for ink and divine substance is no coincidence. It reflects a profound understanding of creation. The Andalusian, Ibn ‘Arabī, compared the world to a book written by God

‘…there did not remain a single place in the whole universe where My word was not inscribed, nor was there any writing which did not come from My substance and My dictation.’93

Quadi Ahmad’s ink reflects the richness of that divine substance. It is an ink worthy of the Qur’ān. In its material composition, his ink seems to acknowledge the saying of Muhammad; ‘the ink of the scholar is more holy than the blood of the martyr.’94

And just as the Islamic scribe prepared his ink with ingredients that reflected the divinity of the Word, so too did the Christian scribe. After all, black could be made from evil-repelling burnt ivory. But, whilst ivory was obviously special, all matter could be revered, as St John of Damascus said in his defence of painting,

‘I do not worship matter; I worship the Creator of matter…I salute all remaining matter with reverence, because God has filled it with His grace and power…Is not the ink in the most holy Gospel-book matter?’95

Craftsmen shared his reverence of matter. For example, in addition to bone and ivory black, they also made black from oak galls, the processing of which was accompanied by chanted prayers.96 And they made black from charcoal, sourced, according to manuals, from beech and willow. But charcoal’s common name is ‘vine black’. It is very unlikely that much black was actually made from burnt vines. Could it be that artists called it ‘vine black’ to reinforce a connection with the Word made flesh – Christ, ‘the vine’?97

The pen may be mightier than the sword, but the paintbrush is also a formidable weapon. Colours, which record the trajectory of the paintbrush, participate in its power. By looking at the hidden nature of dyes, pigments and metals, the following chapters examine the power of some carefully chosen colours.

Notes

1 Theophilus, (I, Prologue), 13.

2Ibid., 12.

3 Cennini, (7), 5, bone black is baked less than bone white.

4 Polydore Vergil, De rerum inventoribus