I really wonder what the finish is on these calipers. It's almost like a bare metal finish because of the matte finish, but I know it's not the natural color of the metal because the color was stripped off my car's calipers during the previous ownership. My guess is that they used some horribly aggressive and acidic wheel cleaner for chrome wheels (car came with chromed OEM wheels) that ate the finish off the calipers. My calipers were a bare metal silver on the front side and still had the original charcoal gray finish on the back sides that probably didn't get hit so hard with the wheel cleaner.
On the Murci, it almost seems like they used a laser to etch the Lamborghini logo onto the caliper, but I can't be too sure of that. I did notice the Lamborghini script was etched into the caliper slightly, so that's why I think it was laser etched from the factory. I am sure I will have to use vinyl stickers to recreate the logo.