As we have seen in other blog posts before, recipes for counterfeits, imitations, and ersatz products were fairly common in the early modern period. On the other hand, there were recipes to detect the results of such deceit, such as this recipe to determine whether wine had been sweetened with lead or not. This testing of products was not only relevant for consumers and apothecaries, but also for artists, as appears from an eighteenth-century artist’s manuscript I have been studying recently.

Mattheus Verheyden or Verheijden (1700-1776) was a successful Dutch portrait painter. The son of the painter Franck Pietersz Verheyden was orphaned at an early age, but thanks to his late mother’s fortune he received training as an artist and soon he became a sought-after painter in the upper classes, and made many portraits of regents, clergymen and royals. In the Rijksmuseum Research Library, a manuscript ‘art and recipe book’ attributed to him is kept (call number 319H17). Written in a neat hand in an unruled notebook meant for music notation, Verheyden recorded almost two hundred pages of recipes and instructions for artists. On the title page he wrote: “Art and Recipe book, for painters and etchers &c., brought together over time and with diligence, by M.V.H.” Some of the instructions come from well-known artists handbooks of the time, while the origin of others is not entirely clear.

From the order of the contents of the book, it becomes clear that the quality of his materials was very important for Verheyden. The first ten pages are devoted to various recipes for making ultramarine paint based on lapis lazuli. Yet they are followed by a recipe that does not describe how to make a paint, but how to test the quality of pigments. It reads:

Test, to discover whether the lacquer one uses to paint is good &c. If the lacquer is made of cochineal, it never changes. And if it is made of Brazil wood, &c., it will becomes an orange colour over time. To discover this, take a small grain of lacquer, and rub it with your nail on a piece of white paper, and put a drop of lemon juice on it. Rub it through the lacquer with your finger. If the lacquer remains unchanged, it is good, and made of cochineal. But if it turns an orange colour, it is unstable, and made of Fernambuk, or Brazil wood, and will evaporate over time, and is no good.

Red pigment made of brazil wood was – and is – much cheaper than that made of cochineal. Even today, the latter is four to thirteen times more expensive than the former – crude cochineal sells at about ten euros for 25 grams, and carmine red (purified cochineal) costs about thirty euros per 25 grams, while the same amount of brazil wood pigment costs only about 2.25 euros. The relative instability of brazil wood as a red pigment had been known for centuries, but this recipe gave a quick and relatively easy way to determine whether what was on offer was cochineal or brazil wood.

For an artists like Verheyden, whose reputation depended partly on the quality of the source materials he used for his paints, this was understandably very important. Commercial, ready-to-use paints only became available in the nineteenth century. Although Verheyden’s recipe book never appeared in print as far as we know, it is reasonable to assume that the kind of testing and quality-control described in this recipe was a desirable commodity for painters and other artists who worked with pigments that they bought from apothecaries, herbalists, chemists, or traveling salesmen.