Anthraquinone Blue has become one of my go-to colors and I’ll tell you a little about it and why that is. It is a transparent blue with an excellent lightfast rating. It is very dark in value, an optical black unmixed. It has a strong tinting strength, yet is easily controlled when creating mixes. There are several manufacturers of this pigment and within each manufacturing company there can be options on which PB60 to choose from. Anthraquinone Blue pigments have a reddish cast, which can almost give the impression of a blue violet, some more than others. I had the privilege of helping in the selection of this pigment when Enkaustikos added it to their paint line. It has a balanced reddish cast in mass, but there is a slight hint towards green in the undertone, making it a nice choice for mixing with yellows, even Indian Yellow PY 110 for those deep and lustrous greens.
The name Anthraquinone is perhaps better known by the name of Indanthrone Blue especially with oil paint manufacturers. Other names you might recognize for this pigment in the art industry are Delft Blue, Indian Blue and Faience Blue. This blue is more commonly associated with a deep indigo due it’s dark hue.
Have you ever looked up to the midnight sky and are still able to see blue? That’s what Anthraquinone Blue looks like when extended with wax medium. It maintains a lot of depth and richness without becoming dull. When I was first in art school, I used to wonder how artists could paint the night sky and have it look so luminous. Once, when in Leon, France, I looked up at the sky and saw the exact color I had in my minds eye. Later in that same trip I was visiting Notre Dame Cathedral and was surprised to see the same color used in the interior of some of the annexes. I’m not saying that France is the only place to experience this color, but let’s just say I was at the right place to be so imprinted.
Anthraquinone Blue has completely different properties than Phthalo, Ultramarine, or Prussian Blues. Some artist say it resembles Ultramarine Blue, but I can not agree with that statement at all. It mixes completely differently, it is much darker in value, and does not have near the red cast that Ultramarine Blue has, nor its bright clarity. It is not nearly as vibrant with the green undertones as Phthalo Blue. Anthraquinone Blue is most similar in nature to Prussian Blue (PB27) without the intensity of chroma that Prussian Blue has or the strong green undertone of the Prussian Blue. When mixed with white though, it tends to grey out quickly to a "navy", and if bluish grey is what you are looking for, try mixing it with any of the umbers. Other colors you might consider optimal for mixing with Anthraquinone Blue are Alizarin Crimson PR177 for a nice range of purples, Anthraquinone Orange PO43 for an intense transparent chocolate brown, and any of the Phthalos to make it more brilliant.
What does this all mean to you and why might you want to incorporate Anthraquinone Blue into you palette? First, if you tend to work with darker values or paints with less intense chroma, you might find Anthraquinone Blue a nice alternative to other blues. If you like to extend your paints with a lot of medium to get soft glazes, this blue will maintain its richness and give you the depth you are looking for without being overpowering. This color is a must have if you like to do any kind of encaustic printmaking. It is an exotic, sensuous blue, sure to seduce you with its charms.