Pit firing may be the oldest method for firing clay. The firing temperature is very low and the pieces are primarily decorative, although anciently they were certainly widely used. Typically the pots are piled together in a pit and surrounded by combustibles of all kinds. Depending on what is in the pit, the pots will come out black, grey, green, pink, yellow etc. I am experimenting with “pit” firing in my raku kiln. I wrap the pot, along with combustibles and minerals, in heavy duty aluminum foil. I then fire it to about 1200 degrees, and let it cool. As with all pottery, you rarely get what you expect. Sometimes it is better!