One way of baking much practiced in the East is to place the dough on an iron plate, either laid on or supported on legs above the vessel sunk in the ground, which forms the oven. The cakes baked "on the hearth" (Genesis 18:6) were probably baked in the existing Bedouin manner, on hot stones covered with ashes. The "hearth" of King Jehoiakim's winter palace, (Jeremiah 36:23) was possibly a pan or brazier of charcoal. From this we see that the significance of the Hebrew words translated hearth is not the same as with us.
Main reference: Smith's Bible Dictionary (1860s)
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