In the process of trying to find some photo's I've previously seen on-line of ovens from the time of Chazal I found the work "Hungry Planet By Peter Menzel" by Faith D'Aluisio where we see this example of a modern day tannur:
nan is cooked in a tannur, a traditional Iranian [Bavli] oven. Basically the tannur is a big, round, clay oven
While the description here doesn't mention the cone shape, it would likely still have the halachic status of a tannur. It also illustrates some of Chazal's description of bread baking.
*the nan featured in the photo is pas palter*
