Be aware that if your fire clay absorbs moisture, if it actually does, when you heat it up the moisture will turn to steam and chips of fire clay will fly.

I don’t really have it lined with fire clay. More what I would call, “fire dirt”.   I would have to drive out of town to find clay, and wanting to see how well the shallower pot worked, I just busted up a small scoop of dirt and packed it in the holes. 
 

But yes, it did spit out quite a lot of sparks when I used it after the last rain. 
 

The shallower pot is much better. In a few weeks I will take it back to my dad’s place and patch the top with pieces of scrap.