Has anyone else every played with concrete micro-fibers? I have been adding them to my concrete while pouring in our crawl-space, and it really changes the way that the concrete 'clings' and once it is cured it really does seem much stronger. My DW and I have been looking at variations of flooring systems. She really wants black slate or something close to it. And then while setting up the "heat-shield / fire-safety" border around our wood stove, I got to thinking and I threw some black concrete pigment into a batch of concrete and I just made some flagstones outside just to see what they would look like. Well it is really 'black'. and this stuff is much cheaper than those concrete-fiber boards they sale for putting underneath a wood-stove or against the nearest wall. So I will be pouring a 8' X 6' pad of black concrete for underneath the wood-stove. Now looking at these flagstones that I poured, the DW and I are thinking that this would work for the entire house. Just a half-inch layer with lots of fiber in it. What you do think?