If they were mining this hard metal, what did they use it for? Wouldn’t some artifacts have turned up if they were smelting it?
As I recall, they still weren’t using metal swords/spears at the time of the Euro invasion.
The researcher in the article said it was used for high-status individuals to show off; in the case of ochre, it was used in the Americas as body adornment (particularly for the preparation of the dead) and painting stuff. That’s similar to what it was used for elsewhere in the world — particularly in Europe, the Mediterranean, the Mideast, and Africa. :’)
The Spanish were looking for precious metals and for gems; they had firearms (at least some of which were made of bronze) and steel or iron edge-weapons. In Bernal Diaz, the natives of Mexico and Central America wore cotton armor, which was pretty adequate for their uses until they met the Conquistadors. They used arrows and spears in great quantity, but I don’t think Diaz comments on the materials used for those. It’s at least possible that the heads of the projectile weapons were copper, which is lighter weight than iron and would therefore have had greater range.
Also, iron rusts, and may have just seemed like more trouble that it was worth.