Staining watercolours will immediately absorb into the first few layers of the watercolour paper before the water has had a chance to evaporate. These colours, once applied, are difficult to remove so that it isn't possible to get back to the white of the paper, this may be a bit of a nuisance if you have made a mistake. Beginners should probably try to avoid using them. Staining colours mix extremely well with other staining colors, but when mixed with non-staining colours they have a tendency to stain the non-staining color and can dominate the overall color of the mixture. Staining colours tend to be the newer colours rather than the traditional inorganic colours. Viridian and ultrmarine blue both lift well. Windson & Newton produce a lifting preparation which will help windsor & newton (practice on a scrap paper first)