Hello, everyone! A friend of mine was kind enough to send me a sample of Paris Blue (PB 27) powder. I got some acrylic emulsion made a dispersion to see how the paint would fare. What he labeled as Paris is to the left, and what was labeled as Ultramarine is to the right. I had to keep images more saturated than they are in real life because if I tried to remove it, color differences between each sample would also diminish.

Powders:

[*] Paris: Pigment was Sky Blue in appearance. Required a lot of pigment to make a significant amount of paint. Highly transparent.

[*] Ultramarine: Pigment was reddish in appearance. Required just a small amount of pigment to make a significant amount of paint.

First of all, this idea that Prussian Blue doesn’t stabilize in acrylics is horsepoop. At least if the pigment on the right really is Paris Blue. What I noticed is that what was called Ultramarine needed less pigment to make a similar amount of paint, but I’m not sure if this is how Prussian Blue works in acrylics, similar to how Cerulean Blue (PB 35) has much lower tinting strength in acrylics than in oils.

Something that surprised me a lot is how reddish both pigments look in acrylics. I also made some oil paint (not shown here) and these pigments will turn cyan in tints instead (but not in masstone). This Ultramarine Blue (PB 29) seems to match a French variation.

What bugs me about Paris Blue is that I compared it against some Prussian Blue I have and it’s significantly redder, even in oils. I tested it against Cobalt Blue (PB 28) and Cobalt Blue seems greener. Against some Prussian Blue (PB 27) from another brand, it felt significantly redder. It’s still a primary blue, but Phthalo Blue seems almost teal-ish compared against it, even a blue shade (PB 15:1). I’d say both shades of these are similar to Ultramarine in acrylics.

Do you guys have some Paris/MILORI Blue so we can draw some comparisons?