Cobalt Chromite Blue
Colour Number: 26
Pigment Details: Cobalt Chromium Aluminium Oxide / Colour Index Pigment Blue 36 (C.I. PB36)
Cobalt Chromite Blue Professional Watercolour is prepared using the mixed metal oxide inorganic pigment, cobalt chromium aluminium oxide. The pigment has been selected for its purity, light fastness and intense green-shade blue hue, making it ideal for use in A J Ludlow’s Professional watercolour range.
The crystal structure of cobalt chromium aluminium oxide is similar to cobalt (II) aluminate (which corresponds to the formula CoO-Al2O3), except in this case, the Al3+ cations are partially replaced with Cr3+ ions. The incorporation of chromium (III) in the lattice gives the pigment its greenish blue hue. The resulting spinel lattice is formed around the oxygen anions (O2-) arrange in a cubic close packed lattice and the metals occupy the octahedral (Co2+) and tetrahedral (Cr3+, Al3+) sites in the lattice.
The cobalt chromium aluminium oxide pigment is often described as “cerulean blue”, but its colour is a greener-shade blue than that of the traditional cerulean, cobalt (II) stannate.
|Brand||A J Ludlow|