Hey that is a nice building, but were are the doors? All you have is the dome, but how to get in there?
The windows should be transparent and reflective.(though you can keep the color) and since windows are reflective they will reflect the surroundings, so you might want to add some clouds and i guess make kind of the same weather as in the reference link you gave. As for the metal, i cant help you with that…but i hear alot of people use http://www.cgtextures.com/ for their base textures. You can always go with procedural ofcorce.
Looking forward to the final render!