37.1 Fundamentals
Color as a means of expression is one of the oldest cultural achievements of mankind. The preparation of colors, the collection and production of pigments, dyes and binders are among the earliest verifiable creative processes. It is a basic prerequisite for people to come to terms with what they have experienced and to capture it in a picture. This cultural asset can be traced as early as the Upper Paleolithic and appears in the cave paintings, for example, of Lascaux (France) or Altamira (Spain). The following remarks refer mainly to the occidental cultural area.
When dealing with historical pigments, dyes and formulations, the reconstruction from our present perspective is often ambiguous. The former manufacturing processes reflect the view of the practicing artist or craftsman in past time. A scientific approach as we know it today is an achievement of modern times.
Different sources are used for the reconstruction of historical painting materials today. In addition to original coatings of paint on various picture carriers, which can be traced far back in different cultural circles, we have today particularly technical writings, recipe notes or paintersâ manuals that reflect the everyday situation of the former craftsmen. Early directly transmitted written sources date back to the Middle Ages. The Lucca Manuscript from the ninth century or the Mappae Clavicula from the twelfth century is among the oldest monastic manuscripts that have, however, more the character of unsystematic collections [1]. Since ancient times, there have been indications how painters worked and what technical tools they had. The interest in these sources arose with the beginning of classical studies in the eighteenth and nineteenth centuries [2].
Surviving works of art are also complex testimonies for the materials used in the respective times and regions or in the corresponding cultural spheres. Modern nondestructive scientific examination methods such as neutron diffraction, X-ray diffraction or infrared spectroscopy help to identify historical painting materials. The multilayered structure of a work of art can also be traced using these methods.
It is possible to investigate how the artists selected, procured and processed the materials, but it is almost impossible to translate the recipes into the language of todayâs chemistry. The chemically complex raw materials that were used are of low purity in the modern chemical sense and are not always comparable due to the natural locations where they were found.
In addition to the knowledge about the processing of these raw materials by the former craftsmen, extensive experience of botany is required, for example, for the plants that were used for art purposes. Different properties of a plant raw material are attributable to the time of harvesting or to the place of growth. In the same way, the knowledge of zoology for the animal raw materials, mineralogy for the mineral pigments and also metallurgy is required.
The old master recipes often require extensive interpretation, since the terminologies and the manufacturing processes described do not correspond to todayâs materials and production processes. Natural raw materials of mineral, animal or vegetable origin provide the basis for the painting materials produced in more or less complex processes.
Particular attention will be paid here to the extraction and process...
