To me, earthenware is always "proper clay" - the sticky reddish stuff that squelched between your childhood toes! It is also the traditional material for British pottery, with the old pottery or brick making centers such as Verwood, Burseldon and Bishops Waltham just to the south of me, a line of hills segregating our chalky soil from the clays of the Hampshire Basin to the south. It fires to rich red-brown tones, and throws beautifully.
I use it with a variety of dry glazes and slips, varying from a smooth silk finish to a rough, sandy surface. These complement the matt colour of the clay, and its earthy character. Sometimes I may use the highly reactive cryolite to attack the surface. I may also impress leaves and other found objects into the clay, leaving their mark, and sometimes also used as a stencil for the slip. The glaze of slip may also be scraped thin or even removed from some areas to reveal the underlying body.
Whilst most of the glazes used are not safe for food or for putting in the dishwasher, where one of these pieces may be used as a vase or for storing objects I may coat the inside with a glaze, both to ensure that the ware is impervious to water, and to apply a protective seal.