Thread: Dirty white stone

In the ebay auction for this stone it appeared to be a blue stone with an oily surface. I knew it could be pretty much anything beneath the surface but I wasn't expecting lapping would reveal a white stone. It measures 14.8 x 4.9 x 2.5 cm and the slurry is white. I've only finished the first stage of lapping, I got tired because this stone is hard.

It feels as smooth as my Guangxi to the touch so I'm looking forward to test it.

Does anyone have an idea what this could be?

Total stab in the dark here, but possibly some sort of Arkansas?

Hopefully someone with more knowledge will chime in..!

It could be a lot of things, of course, but it looks a bit like the lithographic stones I used to see when I made deliveries to printers workshops many moons ago. I believe they were some sort of very hard limestone, blue/white in colour, and often very greasy with the lithographic ink that got rolled out onto them.

Be interesting to find out what it really is!

Regards,
Neil

If my ex-wife were a stone, that would be a good description...

(/end useless post)

Just a personal thing, but I don't go by how a hone feels to the touch, unless I'm checking hardness. I can't tell the difference between hones by touching them, and I don't really think anyone can, especially if you are comparing to a hone that is at least 10k. See what it does to steel (removal, scratches, edge feel) and go from there.

Once broken in I can feel a difference between most of my hones if I give them a good rubbing with my fingers. It's not exact, but it does give me somewhat of an indication of how fine a hone is. The real test is of course with metal. I realize it doesn't say much of a freshly lapped stone but who can resist to feel the result of a good lapping?

It does look somewhat like limestone, perhaps it was used for printing Rorschach ink blots

Originally Posted by Piet

Once broken in I can feel a difference between most of my hones if I give them a good rubbing with my fingers. It's not exact, but it does give me somewhat of an indication of how fine a hone is. The real test is of course with metal. I realize it doesn't say much of a freshly lapped stone but who can resist to feel the result of a good lapping?

It does look somewhat like limestone, perhaps it was used for printing Rorschach ink blots

Now then Mr Piet, would you care to tell us what you see in that blot....

The first post was after lapping the stone with a worn diamond hone. That really left it smooth. The diamond hones I use are cheap ones and not very flat. Hence I switch to sanding paper for the final stage of lapping.

I lapped it all the way up to 800 grit, the endresult was smoother than a Coticule and almost as smooth as my Rozsutec. I honed my test razor on it and shaved with it after stropping (no paste). I actually don't like shaving with an edge that's coarser than one coming off of my Guangxi but the shave was alright.

The following is a description of the characteristics of the finest Lithographic Stones, found in Solenhofen, Bavaria. "The best lithographic stone hitherto found, breaks with a conchoidal fracture; it is of homogenous texture, it's colour is of a uniform and yellowish white, being nearly similiar in appearance to the hone stones used for razors; on breathing on them, a slight aluminous smell (similiar to that of pipe-clay) is perceived."

Incidentally, razor hones were made from Solenhofen Lithographic Slate, and were generally well regarded.

Kindest regards,
Alex