What’s the difference between these two granulating light blues?
I compared both from Da Vinci. Da Vinci’s Cerulean Blue Genuine (PB36) is quite granulating and slightly higher chroma than other Ceruleans I have tried. Da Vinci is also the only company that still makes a Manganese Blue mix with the original granulating pigment PB33, though it is mixed with PB15 (Phthalo Blue).
Comparison
Hue: Both are mid- to light-value blues with a moderate chroma and a slight green undertone. MBM is slightly higher chroma with more green undertone.
Opacity: Cerulean is more opaque.
Granulation: Both are granulating. The Cerulean Blue has large, interesting granulation. Genuine manganese blue PB33 is said to be very granulating but this mix appears to be mostly PB15 as the granulation is somewhat limited and small.
Toxicity: Both are toxic, to varying degrees. CBG’s pigment, PB36, is a heavy metal cobalt, but a relatively low-toxicity one. MBM is a mixture of a toxic manganese pigment PB33 with a nontoxic phthalo pigment PB15. I tend to assume that MBM is significantly more toxic to the point where I am more careful about how I dispose of the water and washing my hands after use, etc. Which you should do anyway I suppose, but Cerulean is more within the normal realm.
Brush Feel: In these specific formulations, I find Cerulean to be a fairly pleasant texture and strength, while MBM is a bit gummy and weak (though not as much so as the MB hues I have tried).
Color Mixes
Hansa Yellow Medium (PY97)
Cerulean’s mixes are much more muted and look like blue and yellow at the same time, whereas the MBM mixes are more vibrant green. Oddly though PB33 is so granulating, the mixes with CBG looked more granulating.
Quin Red (PV19)
Similar, but the CBG mixes are higher chroma. There is a certain dullness to the MBM mixes, perhaps because the hue is more green-toned. Both mixes have magical, floating blue granulation.
Cobalt Violet (PV14)
The CBG mixes are a bit cooler and deeper. Both have extreme granulation. I tried both these mixes because PB33 + PV14 was Zoltan Szabo’s favorite snow mix, but I like the Cerulean better for this use case.
Terra Cotta (PR102)
Earth mixes with Cerulean make fairly pleasant browns and grays but the ones with MBM didn’t do it for me.
Conclusion
Manganese Mix is unique and that made me want to try it, but I have to say that in pretty much every respect I liked Cerulean Blue better.