Plaster molds wear out from use. Sharp definition becomes dull. Even if used there could be ways to distinguished newer ones by small detail.
Porcelain ( kaolin ) clay is a mixture of :
5 parts kaolin
3 parts feldspar
2 parts flint
If you want it to be transluscent add calcined bone.
It is mixed with water into a slurry the mold is coated with a defloculant to prevent the clay from sticking to the plaster. The mold is held together with whatever and the slurry is poured in and set to start the casting process. The plaster pulls water out of the clay and thickens on the surface of the inner mold till about 1/8th inch thick and the rest of the slurry is poured out to use again. The molds are set aside to dry and when the clay is leather hard the mold is separated ,the mold lines removed and the piece is bisqued fired at 1850 degrees fahrenheit. After that it is spray glazed with a clear glaze and fired to 2340 degrees (cone 9) and bingo you have a figurine.
The molds must be master molds to make secondary molds to be exact copies but as stated they wear out quickly.
Can you tell I have been a potter?
Porcelain ( kaolin ) clay is a mixture of :
5 parts kaolin
3 parts feldspar
2 parts flint
If you want it to be transluscent add calcined bone.
It is mixed with water into a slurry the mold is coated with a defloculant to prevent the clay from sticking to the plaster. The mold is held together with whatever and the slurry is poured in and set to start the casting process. The plaster pulls water out of the clay and thickens on the surface of the inner mold till about 1/8th inch thick and the rest of the slurry is poured out to use again. The molds are set aside to dry and when the clay is leather hard the mold is separated ,the mold lines removed and the piece is bisqued fired at 1850 degrees fahrenheit. After that it is spray glazed with a clear glaze and fired to 2340 degrees (cone 9) and bingo you have a figurine.
The molds must be master molds to make secondary molds to be exact copies but as stated they wear out quickly.
Can you tell I have been a potter?
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