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
Polymer clay contain a basis of PVC resin and a liquid plasticizer, making it a plastisol. Polymer clay plastisol is also categorized as a plastigel because of its rheological properties. It is a high yield thixotropic material; when a sufficient force is applied the material yields, flows like a viscous liquid until that force is removed, whereupon it returns to being a solid. This plasticity is what makes it useful as modeling clay as opposed to putty or paste. Plastigels retain their shape even when heat is applied, which is why polymer clay does not melt or droop when oven cured. Various