Color temperature is one of the most important aspects to oil painting. Oil paints are made from natural materials from the earth, so all oil colors have life making them warm, cool, or neutral. Each color of paint has molecular properties on how the electrons move around the nucleus.
Warm colors move exo-centrically, cool colors move endo-centrically. So this means that warm colors appear to be coming closer to the viewer, and cool colors appear to be moving away.
Neutral colors have a mixture of both electrons causing them to counteract each other and neutralize the color. You want to avoid neutralizing your color unintentionally by mixing warm and cools together. You can utilize these properties to create depth and oil paintings that are ALIVE!
Acrylic paintings, or neutralized oil paintings don’t stand out as much as oil paintings using warm and cool colors intentionally, and they appear flat and lifeless. Over time you will become fluent in color temperature, by just using many colors and being conscious about wether they are warm or cool. You can also organize your paints into warms and cools, by labeling them and separating them into two drawers or containers, so you don’t forget. This is really helpful to become fluent in color temperature.
Through all the brands, each color maintains its properties. In other words, Alizarin Crimson, no matter what the brand, is cool, so it can be used in areas you want to recede.
To have a perfectly balanced palette, you’ll want to have at least one yellow, orange, red, green, blue, and purple in both warm and cool, plus white, which is neutral. This is your standard basic palette that will allow you to mix almost any color you want. From this basic palette you can add other colors.
Warm Colors:
Indian Yellow, Yellow Ochre, Cadmium Yellow Medium, Radiant Yellow, Transparent Yellow Oxide, Cadmium Orange Deep, Transparent Orange, Burnt Sienna, Transparent Red Oxide, Pyrelene Red, Radiant Red, Blush, Cadmium Red Medium, Sap Green, Phthalo Emerald, Radiant Green, Cadmium Green, Radiant Blue, Ultramarine Blue, Phthalo Blue (Gamblin) or any brand Red shade, Cobalt Violet, Van Dyke Brown, Ivory Black, Warm White
Cool Colors:
Transparent Yellow Medium (Rembrandt brand), Transparent Yellow Earth, Cadmium Yellow Light, Radiant Lemon, Cadmium Orange, Radiant Magenta, Alizarin Crimson, Quinacridone Red, Quinacridone Magenta, Phthalo Green, Viridian Green, Turquoise, Phthalo Turquoise, Phthalo Blue (green shade), Prussian Blue, Paynes Grey, Quinacridone Violet, Dioxazine Purple, Radiant Violet, Raw Umber, Mars Black, Cool White
Neutral Colors:
Titanium White, Radiant White, Chromatic Black
For more warm/cool color lists and resources visit this link on Gamblin Colors