In Search of the Lost Cyan: Manganese Blue
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 with a mixture, 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.
In Search of Cyan Paint
I was working on painting a brilliant blue sky when I realized that no blue in my paintbox made a really bright cyan. Cyan 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 the local art store to inquire about this section of the color gamut. What they said confirmed my suspicions-- there really isn't much at this end of the gamut as far as pigment. That day, I purchased Cobalt Turquoise (shown at the 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. 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, you can get pale blue, but not a good cyan.
A Brief Review of the Blues in the Paintbox
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. 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, in opaque media, one must mix it with white to reveal it's "true blue" tone. This results in a duller, less saturated, bright baby blue. It takes a lot of white to raise tube Phthalo to a light cyan and often destroys some of the vibrant blue-green character. The resulting mix is a chalky pale color. Even with the addition of yellow (mixture 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. If you can find Phthalo Blue 15:3, this will come close to Manganese blue. 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 than cyan. 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. 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. Cobalt Turquoise mixed with a green-leaning Phthalo (like PB15:3) is a good way to get close to cyan. The resulting mixture did not have the same dullness as mixing Yellow into the Phthalo PB15 or PB15:1 (there is a technical explanation for this), nor was it as chalky as simply adding white. Cobalt Turquoise should not contain white, but is naturally a paler pigment.
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. As I mentioned earlier, PB 15:3 comes very close in hue, and if you can find it, PB16 or PB17 also get close to cyan.
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? Leave a comment below.
I'm interested in hearing if you've also noticed this missing color swatch from the painter's color gamut.