They said on the stream that it would be metal =) I hope it comes with a chain as well, and that the chain is rigid enough to make it stay the right way.
I have a witcher medallion I got from a 3D-printing website, made from plastic, but the chain I have for it is a bit thin, so whenever I bend over or do a slight jump or even walk at a particularly brisk pace, it swings out from my chest and more often than not, swings back with the face facing inward =/