http://www.youtube.com/watch?v=lAuvsTJNHJE
 
The rulers of the Pre-incan societies dressed like that. A nose piece, ear pieces, headdress and breastplate made of gold and sliver.

I only showed the suits because they were the most impressive of the museum´s collection, but there are some other things I have recorded.  
 
There are hollow statues made of gold/copper, silver/copper, gold/silver/copper alloys. They explained how it was heated, then cold hammered until the desired metal came to the surface. And you mention that on your paper as well.
 
All the mannequins you see are approximations since the nose piece, ear piece and crowns are mismatches, they don´t belong in the same set. The exception being the very last mannequin, only the nose piece is missing from that set. You can tell from the patterns on each set.  
 
For the clothes beneath the metal, the rulers used the material they favored on the region, being of course made from the finest materials. Some Tunics were made of the wools of camelids or cotton, another high class tunic I saw at the museum was covered in the feathers of certain birds, and these were considered as precious as gold.      

Thanks Rockman for the Great pictures. I was going to say that they were probably decorated with multitudes of colorful birds feathers and some of the nobility probably had capes made of colored birds feathers. They must have been a very colorful and impressive looking people.