good start, nice design. You should switch to viewport 2.0 in maya and enable anti-aliasing to get rid of all those nasty jaggies Next and main issue is it feels very flat right now and there is little material definition to help separate your surfaces. I'd start with the metals adding more vibrent contrasting colors, highlights and low lights to make the surface appear reflective. Remember not to paint in blackish colors, between the metal I see some very dark colors. These are just initial thoughts to consider, I'm not largely experienced in hardpainting
Hey Manu12el, I think that you might need to add a few more polygons in areas that are popping off of the book. It looks like you've got the extrusion working for you on the gold clasp-thing at the spine of the book, but it could really use a little bit of attention on the gold corners of the cover (maybe extrude some faces where the gold is, to give it a more embossed look?).You have the lock that is floating on the side, which you might want the rope to travel through. If the rope needs to be modeled out, it might be a little easier to fix this instead of using a plane. Is the crumpled paper on the side of the book a single plane? If you're able to up the poly count a little, I would put some edges in there to give it a slight bend where it's being crumpled up. More of a side thought that a critique, but the bookmarks sticking out of the pages seem really rigid. If it's an older book, it would be really cool if they used something more like ribbons, or a type of fabric that had a little more fluidity. It's definitely a great start, so keep it up!