@hector: here's what I mean
http://www.youtube.com/watch?v=W4HLJ80VHwQhttp://www.ehow.com/about_6152629_ceramic-vs_-steel-plate.html
So yes its lighter and has its advantages, like absorbing a bullet rather than making it richocet, but it is not durably stronger than steel or most metals. Just a 'for your information' tip before you commit to this ceramic idea. It sounds good, but maybe not as good as you would've hoped.
edit: In my opinion, you might want to even capitalize on both of their advantages by using steel surrounded with the ceramic, like how the tanks are built. That's only if you're not afraid of the magnetic weakness that comes with steel though.