Nice little article here which explains what Cloisonné is, (Cloisonné is a form of enamelware) which a surprising number of people are unfamiliar with. Another article on the The Antique Marks Blog entitled “Antique Cloisonne Ware – Collectible? Popular? Profitable?” also gives a bit of the history associate with Chinese cloisonne and also Russian cloisonne.
I also stumbled across a nice video on Youtube of a cloisonne enameling factory in Beijing which shows the whole process quite nicely.
Then there is the cloisonne page on wikipedia of course, which also has some nice examples of antique cloisonne. The Art of Cloisonné details the process of making cloisonne step by step along with some detailed photos of the process and the artisans.