Federico -
Right, it's polishing rouge. It is on the buffing wheel for final blade finish, and applied to the handles (wood or horn) for the last shine. The wood handles are then waxed, which seals it in the wood. If the kami uses a wheel which has just been dressed, there will be much more rouge in the wood. I'm still getting some out of the handle on my Chitlangi. First step, from now on, will be to sand off the wax and use a toothbrush dipped in Murphy's (straight out of the bottle, no water) to loosen as much as I can BEFORE put any oil on it. The penetrants in the oil will sink the rouge further into the grain. This stuff makes the Eveready Bunny look like an amateur - it just keeps on.