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...
Fine bone china is more delicate than porcelain, with a warmer, translucent finish. It is typically more expensive than porcelain. Fine china is produced without the inclusion of bone ash from similar materials to porcelain.
The purest clay is kaolin, or china clay. Called a primary clay because it is found very near its source, kaolin has few impurities and is the main ingredient used in making porcelain. Because its particle size is larger than other clays, it is not very plastic.