Sometimes…
Work in progress
…I’ve just got to paint a monochrome.
The “black” consists of Paynes Grey, a splash of Red Oxide and a daub of Phthalo Green (Blue Shade), mixed into a Regular Gel (Semi-Gloss) medium.
I was taught on my foundation course not to use pure black. In doing so, you risk creating a dead hole in a painting, a pit from which the eye struggles to escape. Mixing a black avoids the pit, creates something more subtle, more mysterious and hopefully, more interesting.