boiling rocks

Have you ever heard of popcorn? It is a hard kernel of matter that has had the water trapped inside it start to boil. The pressure build up from water boiling can quickly split a rock. My own experience with exploding rocks has been in a bonfire in the back yard as a kid but there is nothing sacred about doing it in a kitchen.
 
I've had them explode in a campfire, too. They were part of the fire ring around the fire, and were sandstone, so pretty porous. The water inside expanded and they exploded.
 
i think i'm going to go with the hot water...scrubbing well and apply salt and hot water more approach
 
i highly recommend NOT boiling ANY rocks, especially those collected near water sources.. rocks can absorb water to a point depending on their mineral makeup, and even have water embedded inside. to boil these rocks could cause excessive pressure to build up from the water inside, thus creating a rock grenade with a nightmare of shrapnel and boiling water. of course, its entirely possible to boil a rock without this happening, but you never know.

jrr doesnt want you to boil rocks.
 
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