Does anyone know how to get red color stain from merbau decking out of slate paving?

Question

I have a slate path in the front yard and recently put in some merbau decking along side it. Whilst putting in the decking, the tradespeople left sawdust on the slate, in the rain. The sawdust has now stained the slate, giving it blotches of ugly red coloring. I've tried pressure cleaning it, which helped a little, but didn't really do much. Does anyone have any experience with this type of thing and able to recommend a course of action, other than ripping up the slate?

Answer 1

use a mild bleach but contain it to the marks with plasticine wall etc