A bit later, he experimented with adding some bluing to the lead glaze, in order to counteract the yellowness of the clay body, thereby producing Pearlware . Pearlware has a distinct blue or greenish cast, especially in areas around the foot or handle of cups and bowls where the glaze was particularly thick. Although whiteware became the commonest form of refined white earthenware, both pearl and creamwares continue to be made to this day. In addition to these three wares, British potters made a variety of refined white stonewares or granitewares , often called Semi-porcelains . Because the clays used for this purpose lacked plasticity, and because the temperature needed to fire them was higher than that needed for ordinary whiteware, refined white stonewares are often comparatively thick.
Porcelain is a different material.
Porcelain was invented in China and until the 18th century all porcelains were imported from the Far East. Because of its fragile appearance and the added expense of its manufacture, porcelain was generally reserved for fine tea sets and show pieces. Several have a deep vertical fluted motif, imitating cut-glass. 4 goblet fragments, clear. 3 basal pieces and a bowl.