Best way to remove old coal stains off red soft brick

[markymark2406]

I’m currently working on a project to get the inside of a chimney breast ready for a log burner, I want to show the natural red bricks but they are stained and covered in coal dust stain, what’s the best way to tackle this I have my wire brush and have heard that cream of tartar works?

Help please

 

[ScottTDR]

Yes, I've seen few people using cream. You can also try Baking soda + liquid detergent or vinegar + water.. at least 1 of them can help.