Diamond grinding material - the top class
Fig: Diamond plates and a grinding wheel, partly already a bit rusty
As is well known, diamond is the hardest natural substance of all. You can use it to grind/dress just about any other material. As with CBN, Diamond grinding media is usually purchased as coated plates or grinding wheels. Diamond stones, fortunately, seem to be getting cheaper over time. They are now also available with a plastic carrier. This makes them cheaper and stainless. I hope they are still well level.
See therefore also here:
For comparison diamond / CBN see grinding material CBN - the king's little brother.
There are also recently vitrified diamond stones (engl. vitrified diamond stone). I have never seen one (outside of youtube). They seem to be constructed similar to artificial stones. That is, they consist of a binder several mm thick, but in which diamond crystals are embedded here. So as they wear away, new crystals keep coming to the surface. This is different from the normal coated plates. However, they then also have to be dressed sometimes, which does not seem to be very easy here either. Prices seem to be horrendous and availability poor. And actually, I don't understand why they should be replaced: from the hardness point of view, they really shouldn't wear out? Only the binder is worn out. I have not found accurate information and will not pursue the issue further