Ancient Israelite cuisine aside, and the loaves were baked on the heated surface. People also began placing a convex dome, initially earthenware and later metal, over the pit-oven and cooking the flatbreads on the dome instead of on the ash-covered surface; this type of oven is probably what was meant by the biblical "machabat", often translated as “griddle”. The Persians introduced a clay oven called a tanur (similar to the Indian tandoor), which had an opening at the bottom for the fire, and through which the bread was placed to be baked on the inner wall of the upper chamber from the heat
Masonry oven oven may be wrapped in mineral wool blankets (similar to fiberglass but made from clay or rock and much more resistant to high temperatures and thermal cycling). Mineral wool blankets do need to be covered — either with a reinforced stucco shell, tile, or equivalent. Based on a survey of Canadian clay ovens, Boily and Blanchette suggest an ideal relationship between door and dome height of 63% -- a higher dome will reduce radiant heat, while a high door will allow heat to escape; if the door is less than 63% of dome height, air and smoke can't circulate freely