These came from my Father's garage, they could be from my Grandfather (who did some woodworking), or the prior owner of the house. No way to know now.

So the box of one of these labeled Carborundum is clearly an oil stone (as the back of the box instructs to use oil).

2020-08-08 00.29.34.jpg 2020-08-08 00.29.43.jpg... very dished out.

And this one:
2020-08-08 00.26.09.jpg2020-08-08 00.26.26.jpg