What do I have here - Finisher?

[global_dev]

I've had this hone for a while, couple years. bought it on the bay cheap IIRC hoping it was something else. I thought it was manmade and coarser at examining it when I first got it (smelled a bit like oil), but I'm not so sure its not natural anymore. I finished it pretty finely on some micro mesh

when dry, it's not glass shiny, but it reflects and glistens. it doesn't feel super smooth either.
when wet, it reflects like glass and can see my reflection in the mirror. the smear down the middle wasn't there earlier. the bottom is actually shinier since I tried to prep the top today to see what was going on.

I decided to run I through a test after each Chosera (1K,3K,5K,8K,10K) and it made no discernible scratch pattern until after the 10K. It made no swarf at all. It only "polished" after each hone until after the 10K. the 10K is 1.5u?

it's 100x40x20mm (4x1.5x0.75in) it feels pretty dense and came in a old wooden box that fits it perfectly. It doesn't absorb water. I can see under the microscope it looks like a rock like granite, but smaller particles obviously with some shimmer. its got a reddish haze on one corner that doesn't go too deep. my pictures don't really do a good job of detailing, but maybe you rock hounds have a good guess. any thoughts?

its clearly not black, I thought its a dark grey except for that reddish tinge.

 

[global_dev]

to be honest looking under whiter light its more green than grey. has some of sparkles.

weighs 185.5g

 

[SliceOfLife]

My guess is a synthetic gold testing stone. I bought one a few years ago. It was brutally slow... didn't really remove any steel... just beat the tar out of the edge. Couldn't figure out why it was so terrible... then someone mentioned what it was. Got rid of it but seem to remember it looked similar and behavior was the same... didn't change scratch pattern at all, just chewed the edge up.

 

[SliceOfLife]

Here's the post where I start talking about it. Next few posts detail it and then Alex tells me what it is.
Encyclopedia of razor edge images.

 

[global_dev]

thanks, i looked up some images and sizes. I didn’t immediately see something similar, but perhaps. I put it in some degreaser last night and this morning a bunch of grime had come off the ends and the solution was orange-brown.

yesterday I also took a chisel to it after 1k polish and i did see some initial swarf and scratches

 

[global_dev]

i trial shaved the edge of this thing and it was bittersweet. It was not an unpleasant shave, it was actually pretty smooth and keen. I actually really enjoyed the shave (previous to mystery stone was 10K chosera).

I was kind of hoping that it would be a pretty poor edge as described above as that would have put this question to bed. The solution the stone is sitting is getting much darker, but the greenish color of the stone remains.