The top bar is a mix of insight-live.com/material/173">calcium carbonate and a middle temperature stoneware clay (equal parts). On removal from the kiln it appears and behaves like a normal stoneware clay body, hard and strong. However, pour water on it and something incredible happens: in a couple of minutes it disintegrates (as it rehydrates). And generates lots of heat as it does so.
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Calcium Carbonate, Limestone, Calcination
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