Sgian Dubh
Bill, I'm not sure I really understand what's driving you on this. Is it perhaps just an urge to get to grips with the subject for the sake of it, or is there a practical application you're looking for at the end?

In my case I don't find a need to investigate abrasive much.

A sharpening stone will sharpen my plane irons and chisels, and abrasive paper wrapped around a cork block sands the wood. Files cut metal, and rasps tear up wood.

None of it causes me much angst and so far in life the products I can buy off the shelf are effective enough to keep me planing, chiselling and sanding wood as fast as I need to. Other people have done the work required to supply me with abrading tools-- I just buy them and use them as needed. Slainte.