North-Central Section - 46th Annual Meeting (23–24 April 2012)

Paper No. 6
Presentation Time: 10:30 AM

CALCITE: A HARD HABIT TO BREAK


SHUSTER, Robert D., Geography/Geology, University of Nebraska at Omaha, 6001 Dodge Street, Omaha, NE 68182-0199 and LONDON, Gloria, 7701 Crest Drive N.E, Seattle, WA 98115, rshuster@unomaha.edu

Petrographic analysis of cookware from the Middle East has shown the consistent , intentional addition of crushed calcite to clay in the production of cookware. Samples from Bethsaida, Israel and Tell Hisban, Jordan have been studied to document this phenomenon. Samples range in age from Early Bronze age to Iron/Persian Periods.

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.