stones - india and Arkansas

[Colorado Pete]

I have a bunch of Arkansas and India stones which are worn... they no longer have sharp corners or straight sides.

Is there a way to rehabilitate them? I was thinking that maybe if I rubbed them against emery cloth on a piece of glass, I could get them back to a useable shape. Or maybe hold them lightly against my grinder?

Any ideas?

 

[Alvin in AZ]

You can do any of the above to the Arkansas stones (SiO2) since they are so soft, but the India stones (AlOx) will need at least the hardness of an SiC abrasive to cut it.

Alvin in AZ

 

[Colorado Pete]

old stones

The flattening process worked pretty well. I managed to make flat sides with good corners on most of them.

I looked at the stones and see that some date back to the 1950s--including one that is marked "Red & White Chain Stores", which hasn't existed for a long time (wasn't it a grocery store?). I'm keeping it because it's really nice and hard/smooth.

Another is labelled "Carbo AA120"--which I presume means Carborundum and the grit (I don't know how that got in there--I never use it, it's pretty rough); and another labelled "Bay State 220". Others are just 4" black or white smooth Arkansas stones. I believe the stones which have labels/info on them are probably the man-made ones.

My white Arkansas stone loaded up with emery during this process--so use honing oil and wash them often in solvent while you try this. I got most of the emery back out, but it still looks a little gray.

Anyway, the process works pretty well and the stones are back in a useable condition.