Why were some Copper ASX shares up 18% yesterday?

Copper had a cracking day yesterday on the ASX, as well as global markets. This can be chalked down to the sharp increase in copper prices.

According to Bloomberg, one pound of copper was going for roughly US$370 a month ago, US$393 a pound just three days ago, and now US$404.65 a pound as of yesterday.

The continual spike in price could be due to the cut down of copper production in China, due to a shortage of raw material.