Not all oil paints have the same drying time, or dry at the same rate. The reason for this is that some pigments react with the drying oils they��re ground up with to make oil paint, speeding up the drying time. (In modern-paint manufacturing additives are sometimes use to minimise the differences in drying times between different oil colours.) Faster-drying oil colours are idea for underpainting.

Oil Paint Colours with Fast Drying Times:

Yellow: cobalt yellow, chrome yellow, naples yellow
Umber: burnt umber, raw umber
Blues: indigo, Prussian blue, cobalt blue, cobalt turquoise, manganese blue
Violets: Cobalt violet deep, Cobalt violet light, manganese violet
Green: Cobalt green, Cobalt bottle green
Black: manganese black
White: flake white, neutral white
Brown: burnt sienna, raw sienna

Oil Paint Colours with Medium Drying Times:

Blue: cerulean blue, ultramarine blue, phthalo blue
Yellow: yellow ochre
Green: phthalo green

Oil Paint Colours with Slow Drying Times: