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Sea Shells

Description: CALCIUM


Sea shells are made of calcium and thus can be used to make stoneware glazes. A good starting point is 30:30:30 shells:kaolin:flint or 60 Redart:40 calcium carbonate.

It is possible to calcine the shells to 1500F and then slake them in water. However slaking releases considerable heat and the quicklime produced is caustic and fairly soluble, it likely to produce a glaze with high shrinkage and associated crawling problems.

Related Information


Oxide Analysis Formula
Typecodes Flux Source
Materials that source Na2O, K2O, Li2O, CaO, MgO and other fluxes but are not feldspars or frits. Remember that materials can be flux sources but also perform many other roles. For example, talc is a flux in high temperature glazes, but a matting agent in low temperatures ones. It can also be a flux, a filler and an expansion increaser in bodies.
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