Array ( [status] => 200 [status_message] => Material item [data] => Array ( [material_id] => 1227 [moddate] => 2024-04-16 01:46:59 [name] => Sea Shells [keywords] => CALCIUM [metadescrip] => [chem_formula] => [casnumber] => [searchkey] => [unity] => 1 [ratio] => [ord] => [minedat] => [notes] => 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. [links] => Array ( [typecode] => Array ( [0] => Array ( [link] => typecode/FLS [descrip] => 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. [label] => Flux Source [ord] => 0 ) ) ) ) ) Sea Shells

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Materials for Ceramics

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Sea Shells

Description: CALCIUM

Notes

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

Links

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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