I have four JNATs: a red Akapin (aoto), an Amakusa, a Takashima, and a Yaginoshima with a Mejiro Nagura. I will be getting more JNATs from time to time, as I have it bad.

I've read time and again that a stone shouldn't have any "toxic lines" or something like it. In the natural stone context, what is meant by "toxic"? Is it poisonous? Is it a vein of asbestos? Or is it just an geologic occlusion that affects sharpening? How worried to I need to be were I to find I had a toxic stone? Would I need to get it out of my house? How do I distinguish between a toxic stone and one that is not toxic?

Thank you for any clarification.

Cheers,

Jack