You will want to combine equal amounts of all colors from the color wheel. This will make a neutral gray color. You may have to practice it a few times before getting a good gray.
Pretty much any light colors a mixed together i think. Like light purple and dark a color. Or try a dark dark blue
Mix proportionally dark purple, dark blue, dark green, and yellow, adding white to make the shade of gray you want
Dark grey
When you mix black and white paint, you get gray.
which pigment do we now call kohl- a copper ore or galena, a gray-black eye paint
You can paint them black?
gray
Gray paint contains pigment from both white paint and black paint. The obtain an intermediate shade of gray mix equal parts of both white pigment and black pigment. If a darker shade of gray is desired the black pigment should be increased and the white pigment decreased. If a lighter shade of gray is desirable increase the white pigment and decrease the black pigment.
black white and blue
Out of the choices of malachite, copper, or gray-black, the pigment you would now call kohl is gray-black. Kohl was a form of eye paint used like eyeliner or eye shadow by the Egyptians.
purple and yellow and gray/black
You mix a little of bit of dark blue and brown and you get black. If it looks gray-ish add some green, it should help.
Grey and black are neutral colours. This means you can paint any colour walls in that room and have it look good.
Use black paint on its own, otherwise you will need to keep adding black until the grey becomes black enough. Adding a very dark blue to grey will make a black, but it won't be a proper black, more like a bluey black.
Grey is made by mixing small amounts of black into white paint.