Natural Pigments

An earth color palette, which is the core palette used by old masters, provides both important limitations and advantages. The most significant limitation is the number of hues available in very light and dark values at high intensity (chromatic purity). A palette consisting of cadmium, azo and pthalo pigments does not present this limitation. On the other hand, a palette of these colors requires close control of the value and intensity of each color used in mixtures, and these colors can almost never be used pure. Earth colors, because of their subtle nature (which means they quickly lose intensity when mixed with white or darker colors) and the harmony of their hues and relative values, can be used more spontaneously. Despite the limitation mentioned a great variety of color effects is nonetheless possible; a variety that was considered more than adequate by many of the greatest old masters, including the most famous colorists of the Renaissance.
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Dammar or soft copal varnishes are soft, very flexible and transparent, but dry slowly. These varnishes have a bright appearance and a faint pale yellow color. The color may be varied from golden ...

As a painter who began working about 43 years ago, I have been fascinated by the techniques of the great masters of painting. In the last 20 years, I have spent much of my time trying to understand their approach to painting, materials and specific practice. I have spent much of my time in a relatively narrow area of study, although I have picked up little bits from the early Flemish painters all the way to nineteenth century Academy painting. However, my real concentration has been on those painters that moved me the most in face-to-face ...