The blue used on Chinese vases and perfect for blue skies, the blues in oil paints seemed blessed with some very beautiful hues and this is one of the best.
Introduced at about the same time as ultramarine, Cobalt Aluminate is a synthetic inorganic spinel (i.e. a very high technology metal compound). It is a more greenish blue than ultramarine, with a heavier, more mineral appearance, when straight from the tube. The hues formed from it are correspondingly heavier and greyer, however it has a certain shade which the cheaper ultramarine simply cannot match.
A stunning colour
Very Fast Drying. Semi-Opaque. Excellent Lightfastness. Average Oil Content.