The BMW Nazca has gold-mirror glass, some other show cars have the coating. Think of space suit visor. I've seen a video of a guy brushing on a paint, that turned into a mirror finish on a motorcycle gas tank, but didn't take note of what that paint is. But that was on a solid surface, not clear for a window. Is there something that would create that look, short of asking Oakley sunglasses to put parts into their system?