"Black" isn't. There are very dark browns and blues. Despite what the grandparent posting said, fine painters actually do use black, but not to produce darks (a

"Black" isn't. There are very dark browns and blues. Despite what the grandparent posting said, fine painters actually do use black, but not to produce darks (at least not in oils); the most common use for lamp black (the most neutral of the black pigments) is to create the iris colour for blue eyes in oil portraiture. For deep shadows, though, black pigments are very problematic in that it is extremely difficult to control the transition out of darkness. Because painting is a subtractive medium, one can obtain nearly the same level of darkness using other dark pigments in combination. An "old masters" chiaroscuro typically uses burnt umber plus a warm blue, such as aquamarine, for the great lake of "blackness" from which everything else emerges. Each of those pigments alone prevents the reflection of a rather broad segment of the spectrum, and together they approach true blackness. That, then, allows the artist to manage the transition out of darkness into either a warm or cool tone smoothly by decreasing the amount of the unneeded tone before lightening. Painters who use the Impressionist pallette will never go anywhere near that level of darkness -- their shadows will generally be just below a mid tone using the main colour of the object, cobalt or aquamarine blue, depending on the warmth or coolness of the main tone, and the complementary colour of the main tone, all in juxtaposition rather than as a mixture. The apparent darkness comes from contrast. The same principle, though, is used to create shadows in classical painting techniques (but with mixture) -- a darker version of the main tone plus the complement and often a touch of blue. These rules apply to oil painting. Pure pigments in oil are darker out of the tube than you might imagine due to the optical properties of the oil (which is why white paints are sold in huge tubes). In a medium like soft pastels, which doesn't encapsulate the pigment in a continuous film of a binding medium, blacks are used to create the bottom end of the spectrum out of necessity. Even then, though, a pure black is almost never used.