This massive Narutaki iro-tomae stone is perfect with most efficient with tools, yet so fine that I have been able to hone a wide variety of razors to a shave-ready status.
The iro aspect is a streak of red and yellow that runs from the top surface down through the stone to the back side.
At 1324 grams, and 200 x 75 x 38mm thick, it is not the type of stone to carry around, and I recommend that it be mounted on a wooden dai platform.