Black, Raw Umber, Burnt Umber and Sepia. These are colors I rarely use. They are not part of my regular palette. My reason is that they are too convenient when placed on the palette. I especially do not recommend that they be used by beginners. In my classes, I have seen my students turn their paintings into muddy messes through inappropriate use of these nasty colors. Sepia, in my opinion, is the ugliest color ever devised and a total waste of money. Stunning blacks can be created with mixtures of primary and secondary colors (ex. Alizarin Crimson and Thalo Green; Transparent Oxide Red and Indigo; Burnt Sienna and Ultramarine Blue). Earth colors like Raw Umber and Burnt Umber are easily mixed using combinations of blues and Burnt Sienna, Raw Sienna, and Transparent Oxide Red.