What colors mixed together make a rich brown color?
Usually brown paint pigments are made from different kinds of earth. For example, Sienna and Umber actually refer to the locations in the world where they got the earth to make the pigments. (They are both in Italy, by the way.) To make a warm brown color out of paints that are not brown, you have to use colors from opposite sides of the color wheel. For example, a green and a red combined will usually make some kind of brown, but what it makes depends on the amounts and the particular green and red you use, so you’d have to experiment. A warm brown would usually use more of the yellow-orange-red side of the wheel, and greys or greener browns would use more of the cool side (green, blue, purple). You put two or three colors together, look at the color, and adjust it by adding a little of what it needs.
