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about plaster of paris

Plaster of Paris is a type of plaster which can be used in art, architecture, fireproofing, and medical applications. When people think of “plaster,” they are often thinking specifically of plaster of Paris, although there are a number of different types of plaster on the market including lime plaster and cement plaster. Many art and construction supply stores sell plaster of Paris, and it can also be ordered through specialty companies.

This plaster is made by calcining gypsum, a process which involves exposing the gypsum to very high temperatures to create calcium sulfate and then grinding it into a fine white powder. When water is added to the powder to make a slurry, the slurry can be molded in a variety of ways, and as it sets, a firm matrix is created, creating a solid shape which is also very smooth. One advantage to plaster of Paris is that there is no volume loss, so casts made with this plaster are true to the size of the mold.