Disagree, but it seemed primarily for ornaments.
https://en.wikipedia.org/wiki/Metallurgy_in_pre-Columbian_America
https://en.wikipedia.org/wiki/Metallurgy_in_pre-Columbian_Mesoamerica
What I think is more bewildering is no exploration of the wheel beyond that of toys.
The wheel only becomes useful after you have large domesticated animals you can get to pull a wagon or chariot. They didn't have any until Europeans showed up with horses and oxen.