I have always heard, and been taught, that one should not use rocks from a creek to ring or heat in a fire. The moisture inside heats up, expands, and the rock explodes.

To me, exploding rocks sound kind of cool. So a couple of years ago I decided to try it. Rocks from the bottom of a deep creek, into a very hot fire burning with hickory and oak. Then I hid behind a very big Pine, and waited, and waited. No explosion, no cracks, maybe a little hiss. Repeated the same experiment, same results. Maybe it did happen sometime, somewhere, but I have never seen it, or talked to anyone who has.