PRINTING INKS AND COLORS In the land of forgotten colors On the trail of Cranach, Dürer and Stradivari: chemist Georg Kremer studies and reproduces the paints used by the old masters.
34 print process 22/03 TEXT: HELGE BENDL, PHOTOS: KURT HENSELER
magician’s wares: dragon’s blood, their brushes in pigments; artists, archi- While Kremer’s wife stokes up the dried cuttlefish ink, red fermented tects and even violin-makers today prefer ceramic woodstove in the living room (lab A rice, charred ivory, curcuma pow- these rediscovered natural materials to workers later process the soot from the der, gallnuts, buckthorn bark and walnut mass-produced industrial paints. beechwood fire into bistre, an historical shells, plus bismuth, ink stone, Russian In the mid-Eighties, Kremer purchased pigment previously used to copy bibles), jade, Spanish ocher, rock crystal and dried the old mill at the southwestern tip of Georg Kremer describes his never-end- cochineal insects, as well as an extract from Bavaria. Today, the company and its mul- ing search for historical formulations, for a purple dye murex that costs 2,000 euros ti-million sales support not only Kremer’s natural substances old and new: “Just as a gram. The most valuable substances are family, but also some thirty employees. words have gone out of use in the course of more precious than gold. An alchemist in Although shops have been opened in time, pigments have also been forgotten. the heart of Bavaria, inhabiting an historic Munich, Stuttgart and New York, Kremer Lukas Cranach even had his own apothe- mill in the village of Aichstetten? continues to coordinate his worldwide cary and sold a variety of substances, mix- Georg Kremer laughs at the idea. The business from Bavaria. The quiet nest of ing colors in his studio and using them Ph.D. in chemistry considers himself to be Aichstetten has become the European hub to paint his pictures. But cheaper, indus- a scientific analyst in search of age-old for- of trade in traditional pigments. trially manufactured paints started to be- mulations long since forgotten today. From precious stones, earths, glass, plants and animals, he recreates pigments used by the old master painters in his Color Mill. The 55 year-old has rediscovered the secrets of their manufacture, and now supplies pow- dered pigments to artists and conservators the world over. It all began a good 25 years ago with half a gram of smalt.
“A friend of mine had asked me to help him restore the ceiling of a church in Lon- don,” recalls Kremer. The friend was look- ing for smalt, a blue pigment obtained from glass comprising silica and cobalt ore, which is baked at nearly 1,200 degrees Cel- sius. The last company to manufacture the substance closed down in 1910. Kremer, still a student at the time, went to work and, with the relatively simple production process, ultimately ended up laying the groundwork for his business. Nowadays, conservators are not the only ones dipping Home of a thousand pigments: the historical Color Mill in Aichstetten.
print process 22/03 35 The stuff colors are made of: Georg Kremer makes pigments from minerals, earths, glass, animals and plants.
come more popular in the mid-nineteenth the surface, but also inside the coating found the exact shade of violet in the grav- century as a result of the progress made layer.” Paints of this kind are referred to as el of the French Maritime Alps, which the in the field of chemistry.” “metamers”, which means that their ap- restorers of the Maria Einsiedeln Benedic- pearance changes depending on illumina- tine abbey in Switzerland had been unable The synthetic paints used today in place tion and moisture. Even Kremer’s Color to locate. A shovel, sack and pick are of natural pigments have different prop- Mill shines in subdued or intense shades the tools of his trade, and Kremer always erties than their predecessors, which were of Italian gold ocher and Venetian red, has them at hand in the trunk of his car primarily manufactured from minerals depending on the weather. when he travels, just in case. or organic materials. For example, while With luck, ambition and a broad net- Nonetheless, Georg Kremer produces automotive paints have to be applied as work of contacts, Georg Kremer has man- only a small fraction of the roughly 1,000 uniformly and thinly as possible, artists aged to reconstruct sixty historic colors pigments he sells, buying the majority and conservators strive for the greatest over the last quarter of a century. Once a from a worldwide supplier network. Only possible differentiation and have no prob- century-old recipe has finally been deci- pigments that have to be carefully made lem with greater volume. “My customers phered after tedious study of manuscripts by hand and are accordingly high-priced don’t think in terms of paint per square and books, the next challenge has to be are produced on the banks of the Aitrach foot. Their unit of measure is beauty,” says tackled: the chemist starts searching for River, which incidentally also provides Georg Kremer. the required natural substances. For ex- the old mill with electricity. Stored in Unlike synthetic paints with a sealed ample, he looks for zinc oxides from Peru, plastic barrels, waiting to be processed, surfaced, mineral-based pigments prove to or researches who can supply him with are substances like pyrite, malachite, red comprise tiny crystals that shine like stars saffron, indigo and sandalwood in the de- jasper, rock crystal, azurite, Spanish ocher, when viewed under a microscope. “These sired qualities. The task is an arduous one. cinnabar, lead-tin yellow, purpurite, pigments interact with light not only on It took seven years before he accidentally celadonite green earth and various micas.
“Fra Angelico blue”, the most precious pigment in the world, is made from lapis lazuli according to an old formulation.
36 print process 22/03 Glasses and jars, some with bizarre ingredients, hold valuable pigments that are packaged and shipped around the world.
“Mother Nature has a lot of pretty to a secret recipe, the powder is then 19th century – is available from Georg daughters,” says Georg Kremer democrat- mixed with wax, resin and oils to form a Kremer, but he is only permitted to sell it ically in response to the question of which doughy mass, which is left to stand prior to conservators due to the health risk. And pigment he cherishes above all. The most to being repeatedly dipped in a linen sack animal activists saw to it that the practice valuable is undoubtedly “Fra Angelico in lukewarm water. The pure bright-blue was banned of feeding cattle exclusively blue”, which the chemist named after the pigment is washed out by this process, with mango leaves in order to obtain the painter of the famous frescoes in the con- forming a sediment that is dried in a bowl, unique pigment “Indian yellow” from the vent of San Marco in Florence. When the strained through a hair sieve, filled into animals’ urine. master of the early Renaissance created small plastic jars and finally shipped around the world in the form of a precious Today, Georg Kremer’s product line even powder. It is not a hardship, but an oppor- includes 125 types of glass, each in five A starry sky tunity, for conservators and professional grain sizes. Innumerable jars on the ex- artists to be able to mix the pigments them- pansive display wall in the Color Mill’s of tiny crystals shines selves with additives and binders and thus main office bear witness to the rediscov- have total control over the consistency. ered knowledge of herbalists and apothe- under a microscope. caries of long-ago centuries – and the ma- Knowledge of old formulations is just as terials are still used today for book illus- important to Georg Kremer as knowing trations, watercolors, frescoes, oil paint- his works of art over 500 years ago, his where to find the raw materials in the 21st ings, sculptures and stuccowork. contract even stipulated how much of the century. Take “Bohemian green earth”, for And not to forget, also for making precious paint he was permitted to con- example, a standard color up to the mid priceless string instruments. Experts even sume. Today, one kilogram of the blue pig- 20th century: although Kremer knows attribute the outstanding sound quality of ment costs over 15,000 euros, because it where it comes from in the Czech Repub- old violins, violas and violoncellos in part takes days to convert ground lapis lazuli lic, the grounds are now a forbidden mili- to the special varnishes used in past eras. into the purest ultramarine pigment – tary zone and the pigment is accordingly Many of the secrets of the old polishes only a few grams can be produced from difficult to obtain. “I survive on my good have now been uncovered. Georg Kremer, one kilogram of the stone. connections,” admits the master of forgot- the master of forgotten colors, has a A lab technician first crushes the larger ten colors. For example, where can you primer in his assortment whose chemical pieces of stone in a cast-iron mortar, re- buy carmine when the cochineal insect composition corresponds almost exactly to moving calcareous deposits and pyrite apparently no longer occurs in Europe and the mixture prepared over 300 years ago chips. The material is then re-ground by a the warm red pigment made from these in the workshops of famous violinmakers “jaw breaker” machine reminiscent of a tiny animals is at risk of sinking into obliv- like Antonio Stradivari. ■ nutcracker. In the next step, a fine powder ion? Similarly, no one has been able to get is formed between the rotating metal disks hold of genuine Russian green – with of an electric mill and in grinding vessels which Albrecht Dürer once colored his en- made of agate, only to be collected once gravings – for the last seventy years now. Internet again by the technician and sorted by In contrast, poisonous white lead – which www.kremer-pigmente.de grain size using stacked sieves. According virtually every painter used up until the
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