Ok. I just check mine and I'm seeing them too. I did a quick scrub with a scotch brite and they didn't come out. I've only lapped using the black wet dry sandpaper, so I doubt it is something I've introduced while lapping.

I've no clue if this is a defect or by design as I've only the one hone and have only seen pictures of lithide. That said, it doesn't seem to make a difference in how well the hone works that I've noticed. All the same, I'm curious now.