Two weeks ago I built a fire pit out in the front yard for those late night deep conversations with friends. I use rocks common to Tennessee to line the walls of the pit. One rock I used (and not much of it...thank God) was, I believe, called shale. It is not a very robust rock and breaks easly. Today I broke in the fire pit, and it was blazing pretty good when these shale rocks started to explode. Fragments of rock were flying everywhere. Luckly I didn't use many, so the show was pretty short. Has anyone ever experienced anything like this. Damn when a pice of rock knocks your beer out of your hand it's time to fall back and punt.

Just wondering
Night Dragon

I'm hoping to get up that way again and have one of those evening conversations with you. Lose the shale though. LOL.......... I'm still upset we missed one another the last time I was there too. I should've called you sooner.

shale rock its the layer of rock before you hit coal,oil, or natural gas while there is little to no oil in Tn or AL both are heavy with coal an natural gas deposits an if rocks where blowing off as we call it here in the south its safe to say that your shale most likely came off of a natural gas deposit cause shale burns off coal but blows if it sat over gas and there are test holes everywhere in both states find you some Field stones and sum red clay build your pit out of those you be much happier !

Like Sunchaser said...shale is the last thing you'd hit before oil.
It acts as a sheild in one way, and a combustible in the other. It can block gases, but it absorbs oil...

I wouldn't use it in a fire pit, at all. It makes a nice table top though...lol

BE SAFE BROTHER.

Ride Free
Tweek

 Yea I had to change out some of the rock in the pit. It was getting a little dangerous when ya set to close.
Also made a Fire Pit Table 
Stay Safe
Night Dragon

The new table is looking kool !!!

We have something sort of like that exploding rock out here in the Sierra Mtns

https://youtu.be/yAZ1V_DJKV8 />
this is a good example of it.All it takes is some hot sunlight & cold nights on the bare rock and it starts blasting apart.The big one comes towards the end of the clip. Any exploding rock is always one hell of a wake-up call ..!!!

WOW that was crazy.  I have never seen rocks react that way before. 

Yep Dragon, I have seen this very thing all over the country whilst sitting around many a fire pit. Also, from fires made for sweat lodge stones. Years ago a riding buddy had built a firepit in his new backyard and called some friends over for a BBQ. There were 8-10 of us and the cook fire created no problems but when we built up the fire so we could play some music and drink some beer... All hell broke loose! It started slow, one rock popped and tossed a chip past my ear. Within an hour, we were all sitting farther back and almost every stone had popped at least once, throwing stones in all directions with varying speeds. I stopped by later in the week and helped him tear it down, then we went out and gathered igneous rock (volcanic stone) and rebuilt it.
Any stone will pop if it is wet and is heated quickly (steam inside does it) or is frozen and added to a fire pit while it's lit. Been there, done both lol. So, look for granite, basalt, lava rocks and stay away from the shale, sandstone or any sedimentary & metamorphic stone. "Dark & heavy & rounded, good. Light-colored & flat-shaped... not so good."
"Party on Garth!"
Edge 'RockHead' Walker