Delftware, or Delft pottery, denotes blue and white pottery made in and around Delft in the Netherlands and the tin-glazed pottery made in the Netherlands from the sixteenth to the eighteenth centuries. The use of marl, a type of clay rich in calcium compounds, allowed the Dutch potters to refine their technique and to make finer items. The usual clay body of Delftware was a blend of three natural clays, one local, one from Tournai and one from the Rhineland.[4]
From about 1615, the potters began to coat their pots completely in white tin glaze instead of covering only the painting surface and coating the rest with clear glaze. They then began to cover the tin-glaze with clear glaze, which gave depth to the fired surface and smoothness to cobalt blues, ultimately creating a good resemblance to porcelain.[5
Delftware in the latter sense is a type of pottery in which a white glaze is applied, usually decorated with metal oxides. Delftware includes pottery objects of all descriptions such as plates, ornaments and tiles.Today, Delfts Blauw (Delft Blue) is the brand name hand painted on the bottom of ceramic pieces identifying them as authentic and collectible.