This blog was cross-posted from the SpringerOpen blog.
Imagine a trip to the Norwegian fjords during the country’s long summers. Imagine entering one of the few surviving and silent stave churches, preserved by the National Trust of Norway. Hear your footsteps crackling on the wooden floor. Smell the pine tar that continues being applied on the walls. In a corner, you find what looks like an old open box. It contains rags, dusty small bottles of varnishes, and many, many metallic, fragile paint tubes. How many is difficult to say, but certainly more than a hundred!
You realize that these paint tubes once belonged to the renowned Norwegian painter, Harriet Backer (1842-1932). Among them, there is no black and a lot of blue, yellow and red, probably Harriet’s favourite colours.
You realize that these paint tubes once belonged to the renowned Norwegian painter, Harriet Backer (1842-1932). Among them, there is no black and a lot of blue, yellow and red, probably Harriet’s favourite colours. She must have been picky in the choice of her paint materials, preferring – for almost all of them – the quality offered by the German manufacturer, Dr. Schoenfeld, from Düsseldorf. The whites, however, are from the Belgian producer, Blockx. A whim of hers? Not necessarily… In fact, makers of lead white in the Low Countries were renowned for producing it with the traditional stack process.
This little treasure surely deserves time and attention for a thorough study. You then carefully take (with permission, of course) the wooden box and bring that to the laboratories where you work. In the subsequent months, hours and hours are spent observing the paint tubes under a stereomicroscope and photographing them. To your surprise, the cap of some of them can still be opened! You transcribe what can be read of the labels in five languages of all the paint tubes. Yet, after this strenuous work that has led to an extensive catalogue, you still sense that uncomfortable feeling of incompleteness.
You want to know more about the composition of the paint tubes, their production process, their peculiarities. Unfortunately, Dr. Schoenfeld’s archives (now, Lukas-Nerchau) were destroyed during WWII and no relevant documentary source can be found. Therefore, you start collecting micro-samples (4 mg ± 3 mg) from all the tubes that can be opened. You decide to go to Switzerland to use a machine that you know very well, Inductively Coupled Plasma – Optical Emission Spectroscopy. You take inspiration from a previous work of yours on cementitious materials for developing a new, robust method for the dissolution of the micro-samples and their analysis. It takes five long missions over a period of one year and a half to Zurich to conclude all the experiments.
You find several interesting aspects related to the production of these paint tubes between the end of 19th century and the beginning of 20th century.
You find several interesting aspects related to the production of these paint tubes between the end of 19th century and the beginning of 20th century (e.g., about the compositions of brilliant yellows and the finest crimson lakes, or the many impurities/additions present in the viridian tubes). You hope that, in the future, other colleagues will adopt this technique, so that these interesting results will be comparable.
You are now finally at peace with yourself. You feel that Harriet would have been proud of your work and, even many years after her passing, you know more about her art and passion…
The full scientific account of this (real) story can be found here.