Brown Natural Stone Identification help requested
I'm going to aggravate some people here because I don't have pictures nor do I have the stone here with me at work, but I'm looking for some geology. I may be able to post pictures later.
I recently got a stone off ebay. It came quite deeply-seated in one of those old school wooden coffins. I'm trying to identify it.
Here's what I know about it:
Size is approximately 8" by 1.125" A true rectangle. I don't know depth yet because I haven't been able to get it out from its seating.
It's very hard. Harder to lap than a hard arkansas I recently did.
It's mottled dark brown/darker brown-- and on the whole darker brown than any Arkankas I've seen in person. Initially I thought this was due solely to the years of grease built up on it, but I lapped at least a few mms off of it and the brownness remains. Maybe the oil/grease soaked in this deep, but my gut says the stone is naturally a dark brown. The mottling appears random, not a woodgrain appearance like I've seen on some stones this color. It is very beautiful and has subtle depth of color up close.
it was very smooth when I got it and has roughed up a bit since lapping. The finest paper my local hardware store had was 600. I tried following up with the stone after a coticule and I stopped when I was getting the feeling that I was hitting embedded grit particles. I have more sanding and DMTing to do until I'll know its place in any progression.
My guess is that it's a relatively fine stone. First because it felt that way to my touch and second because someone put the time in to seat it in a wooden box. Just a gut thought more than anything, but hey.
Since searching for "brown sharpening stone" is proving unsatisfying, I'm looking for some stone names to use as leads in tracking its identity down.
So, anyone know possible suspects for a relatively fine, brown, hard stone? It feels very Arkansas-ish to me, but I just haven't seen one this color.
Thanks in advance!