Removing Sealer from Limestone Floor Tiles
After chipping away the areas of cement with a chisel I used an application of Tile Doctor Remove and Go which was left to soak into the stone for a while in order to loosen the old floor paint before steaming and wire-brushing the entire floor. This I followed with an application of Tile Doctor "Pro Clean" scrubbed in with a black buffing pad under fitted to a Numatic buffing machine to further clean the slabs. Next step was to cut back and re-polish the Limestone flagstone using of a set of diamond encrusted burnishing pads fitted to a rotary machine. You start with a coarse pad with a little water, then a medium pad, fine pad and finish with a very fine polishing pad rinsing the floor between each pad.Sealing Limestone Floor Tiles
Following all this treatment the flagstones needed a few days to thoroughly dry out after which I returned to seal them with Tile Doctor "Colour Grow", a long lasting impregnating sealer which enhanced the natural colour of the tiles and turned them from a drab grey to a rich and shining black.Source: Limestone cleaning tips and information