I just picked up two Carborundum hones off ebay. I haven't had time to play around with them yet, but I was wondering if anyone knew what level of coarseness they might be. One is a No. 101A and the other is a No. 102. The 102 seems very old and is extremely small - maybe 1.5"x3.5".

To the touch, these feel a little different than my other barber hones (the tilly beginner set and a Wester Bros. "Di-Fi" two sided hone. Are the Carborundums made of different materials? Would this effect the way I would lapp them? Any info would be appreciated. Thanks.

Jordan