I've just got my stone today, And I've been playing with it all morning.
It looks similar to KenG's. Probably the same vein.
Out of the box it was very rough to hone on. Felt like marbles or grit with slurry, So I lapped it out with a 400 diamond plate and tested again. It still had the rough feel. So I lapped it again to 1K.
It's an odd rock. I've put 3 razors over it. The original 1K razor came off the rock sharp cutting arm hair and after stropping a reasonable HHT3-4, The second one took a lot longer to get it to feel right on the rock, and came away with an edge that refused to cut arm hair, After stropping this went into a really solid HHT4.
The last razor well I didn't use slurry on the second razor, And by the time I got to this 3rd razor the rock is so slow I can't see any material been removed in the water. I did about an hours worth of honing. Off the rock the razor refused to cut arm hair again. After stropping the edge is like lighting. HHT5 for most of the blade (the toe is at a 4). The stone has taken a glass like polish and feels like my arky when honing. No idea what the shave will be like but I'll get to test it later.
The burnish after that 3rd razor is mirror like. It's even reflecting colour. I need to do full shave tests to see what the rock puts on the edge but so far the burnished finish looks slow but very promising. My worry is that edge doesn't feel like a coticule edge.
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