A fundamental classic and very beautiful, just look at the swatch opposite for a minute or so.
Loved by landscape painters, it is easy to control having the subtle tinting power of Cobalt. Greyer than Ultramarine, it possesses subtle hues which aren't found in the other blues.
Officially discovered in 1802, it had been used previously for many hundreds of years in the innovative and secret world of Chinese porcelain. From the excellent Handprint website;
"Cobalt pigments are the "cadmiums of cool," creating hues across the cool part of the colour circle from violet through blue to green, in the same way that cadmium hues extend across the warm colors from yellow through orange to red. This is because cobalt oxide can crystallize with several other common metals (aluminum, titanium, chromium, nickel, zinc, and tin) to produce a broad range of pigment colors that vary in both hue and lightness."
This is a very pure version with a gentle hint of warmth.
Below is a video of this colour being milled at Langridge.
Pigment - Cobalt Aluminate, PB28
Vehicle - Safflower Oil, Consistency - Buttery