Some glazes may be coloured but still show some of the clay body beneath.
Some pottery such as flowerpots may be made without being glazed. Most other pottery items are glazed. Glaze can be gloss or matte finish, with many levels between. Generally a gloss glaze is favoured for tableware due to its easily cleaned surface. Some glazes may be coloured but still show some of the clay body beneath. This may be good if using a speckled clay which you’d like to be seen.