You're thinking of white washing you brick fireplace?
Just take a quart of your favorite Behr or Glidden white paint, add a quart of water to it and you are ready to begin painting your fireplace. I brush this mixture on the bricks and then dab some off with paper towels or old rags. After I get the look I want, I sometimes clear coat it with Behr's Low-Lustre Sealer.
Framed pastel on paper with an approximate image size of 6" x 8"
and a framed size of 14" x 16". From a scene in northern Vermont. It is
framed to conservation standards with acid free rag mat and backing with
UV filtering glass from TruVue.