Blue. There may be lots of blues in your paintbox, but have you ever noticed that one is missing? The gradient of a blue sky isn’t quite the same without a bright blue cyan. Genuine Manganese blue, pictured above but unavailable today, was once a staple in artist’s paintboxes. This "extinct" pigment, can almost be replicated… but not quite. You’ll soon know how to get as close as you can, or find the real stuff… if you’re lucky.
This is part 1 of a 2-part post on why you might be interested in Manganese Blue Paint. Part 2 will cover how to find it.
In Search of Cyan Paint
I was working on painting a brilliant blue sky, which was to be the backdrop painting for a newly-made world, when I realized that no blue in my paintbox (demonstrated below) made for a good cyan. Cyan is a blue that is bright, vibrant, and leans toward green. Cyan is easy enough to create in printing inks, so why not pigments? I decided to take a trip to my local art store to ask an old college art buddy of mine about this section of the color gamut. What he said as we examined every blue available confirmed my suspicions-- there really isn't much at this end of the gamut as far as paint and pigment. That day, I purchased Cobalt Turquoise (far right in the graphic) to help approximate the color for which I had searched.
The Limitations of Blue Pigments In Opaque Painting Techniques
If you are interested in cutting to the chase and surveying your options for the blues available, feel free to skip ahead to the next paragraph. If you aren’t quite convinced about the lack of cyan pigments, what follows may illuminate the problem. To understand why Manganese is helpful, or why one should work to find a good substitute, it's important to note that the need for a better cyan is most noticeable when working with opaque paint handling techniques. I painted for years before noticing the need for a high-saturation cyan pigment besides Phthalo, and it wasn't until I worked on commission in gouache that I began to miss it. As an opaque kind of paint, gouache presents its own set of benefits and limitations, and in other media (oil, acrylic, or watercolor) cyan is not so dearly missed. The standard greenish blue is either Phthalo Blue, which is certainly capable of cyan tones when used in a transparent way or Genuine Cerulean Blue, which has a cyan look but is often not very saturated. As a closer match to cyan, let's look at Phthalo. When it's undiluted, Phthalo blue looks almost black, and a person must either thin it down (to create transparency) or add white in order to mix something like a light cyan. In direct gouache painting, the best option is to mix Phthalo with white, which makes the blue less saturated. So, all of this leads us to a quandary: in order to get Phthalo to closer to cyan, at least in gouache, a person has to add copious amounts of white. This makes the blue duller, less saturated, and less leaning toward green. In short, no cyan.
A Brief Review Of All the Blues in the Paintbox: Or How Close can Blue Pigments Can Get To Cyan?
Ok. So here’s the picture (no pun intended). Following the graphic below, let's talk through the options.
From Left to right:
- Ultramarine Blue: As a cyan mixing color, Ultramarine is out of the question, as it is a royal blue that leans more toward purple. This is known as pigment PB 29.
- Cobalt Blue (Genuine): Genuine Cobalt does not lean as far towards purple as Ultramarine, but it will result in even less of a blue-green color than Phthalo blue. Adding yellow to blue to mix a "green-blue" out of Cobalt will only make the resulting mix duller (a basic principle of subtractive color mixing). This is pigment PB 28.
- Phthalo Blue, short for Phthalocyanine Blue: This is the go-to blue for approximating cyan. However, this can best be done using transparency, which is not really a feature of opaque painting methods. Since this color comes out of the tube almost as dark as a black, one must mix it with white to reveal it's "true blue" tones, which lead not to cyan, but a duller, less saturated, bright baby blue. It takes a lot of white to raise it to a light cyan… often destroying some of the vibrant blue-green character and making the mix a chalky pale color. Mix as I might, even with the addition of yellow (not pictured here) I could not achieve a bright blue-green. The color was either too dark, too muddy, or too chalky. There is a catch regarding the capabilities of Phthalo, but more on this later. Usually Phthalo is pigment PB 15 or PB 15:1.
- Cerulean Blue (Genuine): As a pigment, genuine cerulean is a little “dustier" in its coloration (emitting more red and yellow in its spectral profile than other blues). It won't get any "brighter" than it comes out of the tube, and mixing it with white or yellow will further dilute the blue-green hue that it possesses. True Cerulean is pigment PB 35.
- Enter... Manganese Blue (Genuine): First, many companies sell “Manganese Blue Hue” and that is not the same thing. Genuine Manganese Blue, no longer manufactured, is a clear, bright, and punchy blue that leans toward green, and requires much less white than Phthalo in order to lighten it. If working in opaque media, this property can be useful. (There are other reasons that people like it, for example in watercolor— even though that is a transparent medium— but that is outside the scope of this post). I feel it comes the closest to cyan. If you look at the third row, note how much more "blue-green" the Manganese Blues are compared with the standard Phthalo or the Genuine Cerulean. Two brands of Manganese Blue Genuine are shown here: Old Holland and Vasari. You'll know Genuine Manganese Blue since it is labeled as PB 33.
- Cobalt Turquoise or Cobalt Teal (Genuine): The last in line is, in truth, a green, but a green that leans far enough in hue toward blue that it can be helpful. Before I decided to track down some genuine Manganese Blue, I mixed Cobalt Turquoise with Phthalo to get close to the cyan shade I was seeking. The resulting mixture did not have the same dullness as mixing Yellow into the Phthalo (there is a technical explanation for this), nor was it as chalky as simply adding white, as the Cobalt Turquoise does not contain white, but is naturally a paler pigment. This pigment is PG50.
The Secret Manganese Short-Cut
Now, I am going to cheat, and give you the answer your soul has been longing for, which is, what’s a person to do if they can’t find Genuine Manganese Blue, but are dying to paint those cyan skies?
Before we discuss finding real Manganese, here’s the secret. There one particular formulation of Phthalo that comes very close, but you’re going to have to hunt for it and do some label reading.
[Read this in your head as a whisper, because I am giving you the secret password: It’s PB 15:3.] If that doesn’t mean much to you, never fear. Stay tuned for the next post.
In the next post, we’ll also discuss how to to find genuine Manganese Blue for yourself.
So, have you had trouble painting those cyan tones? I'm interested in hearing if you've also noticed this missing color swatch from the painter's color gamut.