Well, not necessarily deadly “rocks” per se, more like deadly minerals and metals, but here’s an interesting list that kind of scared the crap out of me. I collect rocks and pick them up willy-nilly all the time. How will I necessarily know something is dangerous? Well, I wouldn’t, until I found this list that is. I’ve been planning to get a rock hounding book but not til I make good use of my several other wildlife and insect books. The last one is the best. Good.to.know!