There is only one production version and that one has CERAMICA on the dial. The only actual images of the PAM438 dial (meaning it's not a computer generated image) that has CERAMIC on it are of the watch that was shown in SIHH2012 and subsequently posted on various watch blogs. This is a prototype and I imagine sometimes used to throw off would-be replica makers. Another example of the prototype's features not making it to the production watch is the deployant, which was initially shown in PVD'ed steel but was later to be revealed as plain brushed steel. Why they didn't go this more logical route (as the rest of the watch, even the movement, is black) only OP knows.