A microkernel implements all drivers as user-space programs, and implements core features like IPC in the kernel itself. A monolithic kernel, however, implements the drivers as a part of the kernel...
Porcelain is made with kaolin clay. Kaolin is white clay that retains its white color when fired. It is fired at temperatures in excess of 1300 C and is more fully vitrified than stoneware. It is usually covered with a clear glaze, which allows the white body to show.
However, porcelain, pottery, and stoneware may also be referred to asceramics. Non-porcelain ceramic is typically used for more casual dinnerware, whereas porcelain is commonly used in display objects and other decorative items. A ceramic item is not necessarily of a lesser quality than a porcelain item.