Mixing black

I don't like "formulas" for color mixing. And the reason I don't like them is that some artists are too quick to depend on a formula mixture for black instead of mixing the colors used throughout the painting. The result is often a screaming black hole wherever black appears. That said, here are a few combinations that make pretty decent darks. But remember that the named pigment colors should be a part of the palette used throughout the painting and not stuck on as an afterthought. Use rich pigment in the mixture for the darkest darks. Let the painter beware!

-Alizarin Crimson/Phthalocyanine Green (or Winsor Green)
-Alizarin Crimson/Phthalocyanine Green plus Phthalocyanine Blue for blue-black
-Burnt Sienna/French Ultramarine for Payne's gray mixture
-Brown Madder/Indigo
-Rose Madder Genuine/Viridian/Burnt Sienna for "darks" in delicate paintings where black would be too harsh