This is a helmet I modelled last year, I thought I should try and put into a basic scene. The samples are little low so some artifacts are visible.
Why is it in a library? lol
And you should use a spec map for the metal. 
And change the color of the spec a bit. (orange for instance)
Thanks for your advice AlinB, I will give it a try.
Nice model. Is it just me or does it look like it is embedded in the table?