Aureolin (No. 501)
Inorganic
| Colour Index | PY 40 |
| Drying Speed | Fast |
| Opacity Covering | Transparent |
| Tint Power | Average |
| Lightfastness | Excellent |
| Oil Content | Linseed Oil, Average |
| Toxic | No |
| Conforms To | ASTM D-4236 |
Aureolin (Cobalt Yellow) is a transparent, straw, ochre like yellow with strange yet rich greenish undertones. It was produced in the 1850’s as an inorganic replacement for the unreliable organic yellow gum known as Gamboge. In glazes and thinned layers it displays a Renaissance-like range of muted gold which over whites can be quite fiery. However, in or over deeper layers, Aureolin exhibits a mustardy, heavier patina. Mixed with PV 23 it can make a most remarkable deep gingery colour.