There are different commercial formulations of plasticine and
related compounds, but they all share the same basic properties.
Plasticine and clay are similar in that they are both used for
modeling in additive sculpture, and both consist of very fine
mineral particles held together by a binder. The most basic
difference is that "clay" is bound by water, while plasticine is
bound by any number of oily substances. Also, the mineral particles
in plasticine are primarily calcium carbonate, while the minerals
in clay can be any of a number of phyllosilicates. This presents
the following differences in use: clay begins to dry upon exposure
to air while plasticine will remain soft as long as it is
sufficiently warm. Clay can be fired to become hard and insoluble
in water, while plasticine will first melt and then burn if heated.
Fired clay is often used as a permanent medium in art and craft
applications, while plasticine is almost always only an
intermediate step in making a sculpture that will eventually be
cast in metal, resin, etc.
