CALCITE: A HARD HABIT TO BREAK
Samples include cookware of all types, including cooking pots and trays. Evidence of processing of calcite (grinding, sieving) was seen in uniform sizes of calcite rhombs present in the clay bodies. Calcite improves the ability of pottery to withstand repeated reheating without decomposing during repeated cooking uses. Fine grained calcite also allows higher kiln temperatures, allowing oxidation of the clay bodies, producing more desirable red colors. This practice was in place for thousands of years.
In post Iron Age pottery, a shift to quartz over calcite has been seen. The use of quartz allows even higher firing temperatures and allowed any potter to make cooking ware. They no longer needed access to calcite nodules or other sources of crystalline calcite.