From the article:

"We live in crazy days," said Juan Eduardo Herrera, vice-president of strategy at Codelco, the world's biggest copper producer. "These prices are not here to stay and nowadays they are causing more harm than good to everybody."

When the major real market (i.e. the physical metal) people say things like that it behooves everyone to pay attention.

That's because of the old rule of thumb that profits cause competition and outrageous profits cause ruinous competition. He's terrified that everybody and his brother will open copper mines and crash the market...as is usually the case at the end of (and causing the end of) every commodity boom.
How very true...recent example closer to home: bandwidth and telecom eqpt. Take a look at  this:
The prices of copper are causing more harm than good to Chile because the Chilenean Peso is getting stronger so, the overall competitivenes of their economy is going down.