Ceramic door knobs or Porcelain door knobs were first made in the 1850’s. During the Victorian era these were produced in England in the Staffordshire Potteries in their thousands.
Cheaper than brass they became the door knobs of the masses. The demand for ceramic door knobs was further fueled in the later 1800’s as they were produced in a host of designs.

Art Deco was an international design movement which flourished through the 20’s and 30’s and applied to architecture and consumer products.
The style was popularised by the Paris exhibition of 1925. It caught on after World War 1 and reigned until the onset of World War 2. Influences included Cubism with its zig zags and geometricals, Ancient Egypt following the discovery of Tutankhamun by Howard Carter and Lord Carnaervon in 1922 and Aztec and Mayan Art from South America and Mexico.