When oil paint was first introduced to Europe, the process of making the paint was often referred to as alchemy. There is hardly any documentation from artists who had to mix their own paints from that time. This information was safely guarded, and the formulas/recipes were never written down. With the science and tools we have now, we can uncover how artists created their oil paint formulas but it was generally a knowledge that was kept in the artist’s workshop.
If there’s one theme that runs through the history of oil painting and oil painters, is that they are extremely experimental. You have to be. You’re mixing a variety of materials, oils, pigments, grounds, and solvents to create a lasting image on a canvas. We now have all the proper steps to prepare our canvas and the accessibility of oil paint in tubes to paint with more ease, but it’s taken centuries to get to this point.
I do love the analogy of alchemy to oil paints because it’s the same wording used to describe metalsmithing. There are many materials that have to bind together and specific steps that you have to take to ensure the longevity of your work. It’s complicated and requires a lot of carefulness and precision so as not to damage over time and to preserve the colors that the artist intended for the work.
What are oil paints made of?
Pigment is a powder that can be a crushed mineral found in nature, or as most pigments are made now, they are synthetic. Synthetic doesn’t necessarily mean plastic, it just means that it is not naturally found in nature and is rather a mixture of different pigments to create a new pigment color. One of the earliest synthetic pigments dates back to Egyptians times and was called Egyptian Blue. It was a recipe of several pigments to create a specific shade of blue. Pigment is a permanent color and typically does not mix with water. It needs some other material, like an oil, in order to be used.
There are a variety of drying oils used to mix with pigment powders to create oil paints, but the most common are linseed oil and poppyseed oil. Not any oil can be used as with time, the oil can yellow the pigment and distort the color. Other oils that have been used to create oil paints are sunflower, safflower, soy, and walnut oil.
A Few Other Things
Although not used to specifically make oil paints but are essential to the oil painting process, are something called grounds and solvents. 'Grounds' is a term used to define the protective layer between the canvas and oil paint. The oil in oil paint will seep into whatever is being painted on and could ruin the canvas material (wood, linen) so grounds acts as a barrier between the two. There is a huge variety of grounds, but the one I use is an acrylic gesso which is best for wood panel.
Solvents dilute the oil paint and make it easier for the paint to glide off the brush with each stroke. Most artists layer their paints, starting with a more diluted oil paint base and then build up the layers of paint and use less and less of this solvent. Paint straight out of a tube can be tacky, sticky and thick and so we use a solvent to help thin out the paint and get it to the preferred consistency. I recently made the switch to a solvent-free medium and I'll let you know how it goes. Read more at the bottom of this article under 'Disclosure.'
How are oil paints made?
To create oil paint by hand you need a muller, a large sheet of glass, pigment powder, a palette knife and your preferred drying oil. You begin by mixing pigment powder with drying oil and do it loosely with your palette knife on the large glass sheet. With a muller you slowly work the pigment and oil together until you get the right consistency. This can take hours to get just one paint color, but some artists prefer the process of making their own paints and the saturation of the pigment color. To some, the color that comes from creating their own paints is much more intense. Below is how this artist makes their own paint from pigment powder and drying oil.
Paint from a manufacturer has gone under many months, sometimes up to a year to create the perfect formulas. They check for a variety of issues like how light bounces off the paint, how it holds up after some time, how it dries and if the color lasts, the consistency, getting the right mix of oil to pigment. Pigments do not act the same as the next and require their own recipes/formulas per pigment. Once a pigment has been decided on, that formula has to be mixed exactly how it was done in the lab. Instead of being mixed by hand between a glass sheet and muller, the paint is mixed in between steel rollers. Depending on the pigment, the time that it takes to roll and mix can vary. Some pigments require more time than others and occasionally if the pigment is mixed for too long, the color can turn out differently. They also add binders to ensure that the pigment doesn’t separate from the oil while in the paint tube. Below are two videos showing how oil paint is made by machine.
The more I incorporate oil paintings into my work, the more I’ve become interested in the material. Squeezing paint on to the palette brings about a little burst of excitement, but not all paints are created equal. I’ve experimented with a variety of paint qualities over the last few years and now I purchase paints from two brands that I’ve found meet my standards for sustainability, quality, pigment color, and simply how they feel when I paint with them.
The writing of this blog post made me review a lot of my own oil painting practices. There were issues that came up for me that I just couldn't continue working with and I went down rabbit holes to find the safest and best practices that could still maintain the quality I'm aiming to implement with each piece. With that being said, I've made sure that none of the white paints I use contain lead. I have also decided against using oil paints that have cadmium and cobalt as they are high in metal content (not sure if that is a health risk when it is only in pigment powder form, either way not taking the risk). In the middle of writing this post, I found out that oil paints can spontaneously combust when on rags and that made me get up from my sofa immediately to wash everything with soap and water. Luckily oil paints don't combust on wood. They simply dry.
That's all for now. Thanks so much for reading these posts and I hope you find this process interesting. Let me know if there are any topics you'd like to read about in regards to oil painting or jewelry-making in the comments section.
Britannica, The Editors of Encyclopaedia. "oil painting". Encyclopedia Britannica, 9 Feb. 2023, https://www.britannica.com/art/oil-painting. Accessed 3 March 2023.
Wikipedia contributors. “Pigment.” Wikipedia, 18 Dec. 2022, en.wikipedia.org/wiki/Pigment.
Wikipedia contributors. “Egyptian Blue.” Wikipedia, 8 Nov. 2022, en.wikipedia.org/wiki/Egyptian_blue.
Hoakley. “Alchemy: 2 – the Origin of Oil Painting.” The Eclectic Light Company, 11 Aug. 2016, eclecticlight.co/2016/08/11/alchemy-2-the-origin-of-oil-painting.
Hoakley. “Who Invented Oil Paint?” The Eclectic Light Company, 10 Feb. 2015, eclecticlight.co/2015/02/10/who-invented-oil-paint.
Mark Golden on Paint » 3 Years With Williamsburg Handmade Oils. education.goldenpaints.com/blog/2013/paint-ideas/3-years-with-williamsburg-handmade-oils.
Mark Golden on Paint » Keeping the Williamsburg Touch…. education.goldenpaints.com/blog/2010/general/keeping-the-williamsburg-touch.
Tate. “Oil Paint | Tate.” Tate, www.tate.org.uk/art/art-terms/o/oil-paint.
“Sizes and Grounds - Traditional Oil Painting.” Traditional Oil Painting, 11 Jan. 2022, www.traditionaloilpainting.com/portfolio-item/grounds.