Painter’s Toxicity Part 4 – by David Molesky
Vincent Desiderio, Lily in a Round Chair,
The Missing Ingredient in the Old Master’s Medium.
As mentioned at the end of part 3, I have recently stumbled upon a useful and nearly forgotten approach to preparing oil paint and mediums.
While I was living in Norway in 2006, Odd Nerdrum taught me how he makes his own oil ground with powdered calcium carbonate – commonly known as chalk – and cooked linseed oil to which a bit of siccative has been added. (The New York and German-based store Kremer Pigments makes a product called leinöl firnis which Odd and I both use for this purpose.) In his demo, he scooped a large pile onto a mixing surface, usually a 16 x 20 inch ready-made canvas. (After this surface has been used a few dozen times its surface becomes beautifully textured and heavy from the layers of oil ground – a perfect surface for a small portrait.) When the correct ratios are achieved (I am not giving measurements as there are too many variables to consider: temperature, humidity, and variations in the materials), the mixture of oil with chalk becomes a consistency like a pancake batter. Odd does not use this mixture right away. Instead, he lets it sit overnight so that the oil can seep its way into every craggy surface of the chalk particles. Just before he uses the mixture the next day, he rechecks to see if its consistency is still ideal.
Chalk is rather inert. If you were to consider it a pigment you would say that it has a tinting strength that is close to zero. It’s like an empty pigment, without much color at all. When it is dry it is usually white or slightly yellow. When you add oil to it and mix it into a paste it becomes a grey phlegm-like color. Not an appetizing color in which to work upon so Odd usually adds a tiny bit of oil color and mixes it into the neutral chalk phlegm.
Odd had mentioned that the chalk that one uses should consist of fine granules of slightly varying dimension. I asked why and he explained. It made me happy that Odd, who usually avoids speaking about the technical aspects of his paintings, confirmed in this tidbit that he was mindful how the granule size would affect light refraction. I had encountered this concept before when working with a painter who had trained for a time as a restorer (which in some senses is a kind of forgery). She mentioned that her late husband, also a conservator and painter, insisted on making his own lead white rather than using machine-made store-bought varieties. Apparently, the homemade lead was unsurpassed in its quality to refract light. For example, if all the granules of lead are the same size, there will be a wavelength of light that will be perfectly suited to snaking its way around each granule suspended in the oil, which means that particular wavelength of light will be absorbed into the ground rather than refracted. If the granules are of different diameters then this is unlikely and you maximize the illumination of your paint layers from the ground. (How does one make their own lead-oxide? This painter kept a large wooden barrel in his backyard into which he urinated daily. Bolted to the wooden lid of the barrel, was a large plate of lead. The uric acid evaporating from the urine oxidized the lead and turned it white. He would then scrape this off and grind it with oil to make a paint.)
The concept of oil paint being illuminated from the ground, the light coming from within, has existed from its beginning. You see, oil painting is based conceptually on stained glass painting. At the moment of its invention, oil layers have always been thought of as a transparent layer of color through which light would pass. In this regard, it was important to suspend the pigment in such a way so that light could make its way through to the ground. And this is where chalk comes in. As I mentioned above, chalk when mixed with oil is transparent and devoid of color. It is inert and thickens the oil into a paste.
After having used the oil-chalk ground for a number of years, I wondered if it might be useful as an economical way to extend the volume of my paint. While working on a painting called Octopussian Waystation, a large oil on herringbone linen composition (54×78 inches), I thought “what if I use this ground medium to build up the areas where I want there to be a convex form?” It seemed to work well. As you know, oil paint can be very expensive. It’s possible you could easily brush an entire $60 tube of paint in one stroke. If you were to use chalk medium with this color you could get the same impasto effect for a small fraction of the cost. I thought that during the baroque-era this must have been an invaluable insight when pigments were absurdly expensive and were only obtained in extremely laborious ways.
Agostino Arrivabene – Coniunctio – Sulfur and Mercury, 2017, diptych, oil on wood, 60x50cm each panel
During various studio visits with painter friends, I mentioned that I was beginning to experiment with chalk as an additive beyond my using it in my oil ground. It was first in a conversation with the Italian painter, Agostino Arrivabene, that I realized that this practice was indeed a secret of the old masters, one that he personally unearthed in his reading of many obscure and ancient treatises on techniques of oil painting. He mentioned that in his research he found that chalk was the secret component to the luscious butteriness found in the paintings of Velazquez, Rubens, and Rembrandt.
In fact, he had personally perfected his own secret medium containing chalk and had a sample jar that he gave me as a gift. He let me know the contents and process of making his secret medium and asked me to swear to not share it with anyone else. (Sorry readers, I will keep my promise.) However, I found it to be too complicated (and perhaps over the top, approaching the absurd) in the same way as many of the methods Salvador Dali outlines in his book 50 Secrets of Magic Craftsmanship. Agostino’s mixture had many qualities that were specifically tailored to the qualities he wanted his paint to achieve, like spices you would add to your cooking. He wanted his mixture to have enamel qualities (egg), self-leveling (tree resin), and to not be too shiny (beeswax). Although it seems like I might have just given away his secrets, I myself could not replicate it even with the other information I’ve withheld. The thing is, knowing the microscopic behavior of your materials, knowing the language of them, if you will, will help make you a master chef in a well-stocked kitchen.
While interviewing Vincent Desiderio in his Sleepy Hollow studio in 2016, we started talking about the use of chalk in paint. He had mentioned that he had used it in his mediums for many years, but then switched to using Liquin; acknowledging its toxicity, he preferred the convenience of having the medium ready for use. I asked if he recalled where he had read that chalk had been used by the great old masters and he directed me to an article about Rembrandt and a book about Velazquez.
I will discuss the evidence of these practices and my approach to recreating these thicknesses and viscosities with methods and materials that reflect mindful consumerism in my upcoming presentation on the subject at TRAC2019.