Passing a granite slab or panel under an extremely hot flame (1100 degrees Celcius) generally causes the surface to exfoliate with the outermost grains flaking off leaving a rough textured surface suitable for slip resistant external or internal paving. The crystals exposed this way are much darker than a sawn surface despite having no gloss. Flaming is not effective on Marble, Bluestone or Sandstone because of the differing grain structure.
Flaming of edges is generally not done because the loss of grains at the corners will leave a ragged edge. Any edges that are exposed and should also be textured should be bead blasted or left sawn.