Phthalo Green is usually mixed with extenders and given the name Dark Green. It is such a strong pigment, it holds up well with the extenders. Supposedly, the Phthalo colors are now the most widely used of all color pigments worldwide. Phthalo Green is also called Heliogen Green, Monastral Green, and Monestial Green. It has extremely high tinting strength, is transparent but covers well. Phthalo Green is sometimes used as a replacement for Veridian, because it is less expensive and more saturated. Although it is transparent, when applied thickly it can be very dark. Each jar is16 fluid ozs.