/ck/ - Food & Cooking

>>17521862
The reason jnats are special is because they are a made up of chert and a softer binder. Chert is a form of quartz that acts as a friable abrasive. The binder holds the chert and when you rub steel or a slurry stone it creates a mud or slurry of the chert and binder. The abrasive breaks down and changes shape as you work the slurry, so it gets progressively finer the longer you go.

All stones have different shapes and concentration of the chert, so provide different coarseness, speed, and feedback.

Here's an electron scanning microscope image of the abrasive sio2 and the binder.

Tl;dr nature made the perfect sharpening stone that a majority of synthetic stones have used as a foundation for their own composition.