Quote Originally Posted by SharpMan View Post
How do you flatten your natural stones, those that are very hard? I read some
can kill a diamond plate even. I tried flattening one with sic paper, but noticed
the some of the sick grit that came loose from the paper would get stuck in the natural stone. I could see little black dots in my natural stone.

Sharpman
So you're sure the black dots aren't part of the stone ? If you look under magnification some stones have brownish or blackish dots on them called "goma" they aid cutting strength. If the dots you see are raised & shiny you have SiC particles embedded. I actually like to use SiC powders but mostly for heavy work. On wet float glass they would be the fastest most aggressive way to flatten a natural stone that I have tried. If needed you can remove a lot of stone with 40 - 80 grit & save your diamond plates. I have not experienced any particles embedding in jnats but heavy pressure may be the culprit if you do. I use various diamond plates for lapping after that as it is less messy but SiC cuts fast. Softer powders like AlOx or automotive valve grinding pastes, which are usually a mix of the 2, will work but even the SiC breaks down quickly. The slurry you build needs to be wiped off if stiction becomes a problem or sometimes adding water helps but as I said it is messy.