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.
Porcelain is the term currently being used to refer to the highest quality ceramics. Kaolin is used in the manufacture, and it is usually very delicate. Another member reminded me that the most significant identifying factor for porcelain is it's translucence. You can see a shadow of your finger through it if you hold it up to the light.