The two can be very similar. Both are (usually) non-toxic substances easily made into shapes at home. Typically both are baked to harden them. Salt dough only needs a low heat, true modelling clay needs to be put in the oven at high heat.
Both products can be painted with water colours or poster paints, after hardening into their desired shapes.
Salt dough: you can make in your own home, from household ingredients (2 cups plain flour, 1 cup salt, 1 cup water, optional tablespons of lemon juice and vegetable oil). Salt dough is heavier and the less flexible to work with than modelling clay.
Modelling clay is a product you buy. Its actual composition may be a variety of things. Typically it's made of very fine silicate clay. The default colour is white, but sometimes dyes are added to brighten the product up. However, nylon filaments may be mixed with the clay particles to reduce the incidence of cracks; items made of nylon reinforced clay cannot be fired (baked at heat), though.
Sometimes plasticine (and similar products) are referred to as modelling clay. Plasticine is a synthetic clay-like material, actually made of calcium salts, petroleum jelly and aliphatic acids (a type of fatty acid). Plasticine is the easiest of all these materials to work with in fine detail.
Both products can be painted with water colours or poster paints, after hardening into their desired shapes.
Salt dough: you can make in your own home, from household ingredients (2 cups plain flour, 1 cup salt, 1 cup water, optional tablespons of lemon juice and vegetable oil). Salt dough is heavier and the less flexible to work with than modelling clay.
Modelling clay is a product you buy. Its actual composition may be a variety of things. Typically it's made of very fine silicate clay. The default colour is white, but sometimes dyes are added to brighten the product up. However, nylon filaments may be mixed with the clay particles to reduce the incidence of cracks; items made of nylon reinforced clay cannot be fired (baked at heat), though.
Sometimes plasticine (and similar products) are referred to as modelling clay. Plasticine is a synthetic clay-like material, actually made of calcium salts, petroleum jelly and aliphatic acids (a type of fatty acid). Plasticine is the easiest of all these materials to work with in fine detail.