Was called "Scary Sharp" a long time ago. Or "Plate Glass Sharpening" Sand paper from a auto shop can go to 4000 grit. A little water on a plate glass sticks the sand paper down to the glass & can make metal look like a mirror. I used a piece of granite tile. The trick is to make it as sharp as possible... With a jig to hold the blade at the exact same angle each pass, then reset the angle a little steeper for the next few passes with the finest paper you use. this puts a second bevel angle that is so small you can't see it with out a magnifying glass, but the second bevel will make the edge last for a long time. Samurai swords have been sharpened like that for...for ever. But the old sword makers never told anybody how the swords were so sharp & did what they could do & stay sharp. works great for any blade. except scissors, they are different. As they don't have to cut hard stuff. ( O.K. I have a "Sharpening Problem." everything in the house is close to a razor blade.) But every day & in every way, I'm getting better & better.