Salt glazing was a technique used by stoneware potters to create a glassy surface. When the pottery kiln reached over 2000 degrees Fahrenheit, salt was introduced to the kiln, creating a vapor. This vapor adhered to the silica in the clay, forming a glassy appearance on the pottery. Because of the high temperature at which the pottery was fired, the clay often became non-porous, or vitrified. This, combined with the salt glazing, meant that potters did not have to apply a glaze to the interior of the vessel. It could hold liquids and not seep, unlike earthenware storage vessels.
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