Phthalo Green: A dark bluish green more closely resembles poisonous Verdigris than Viridian. First manufactured in 1927, Phthalo Green has a very high tinting strength and transparency. Many painters have been warned away from Phthalo Green because of its color strength. Consider using Phthalo Emerald, a warmer more natural looking color. Pigment: Chlorinated copper phthalocyanine (PG 7), Vehicle: Alkali refined linseed oil Lightfastness I, TRANSPARENT.