Inorganic – Viridian is about the fastest curing colour in my entire range along with my stack lead white. This hydrated variant of Chromium Hydroxide, introduced in the mid 19th century, is a valued support colour used for influencing greys in the underpainting. The vivid blue undertones apparent in thin layers are soon eclipsed in thicker applications. Landscapists and some portraitists still prefer it to the more brutal power of the Phthalo Greens. When combined with reds an interesting range of blue-greys results. Placing it as local colour in the proximity of vermilion can also have some very interesting complementary effects.