Why is copper so important?
Advantages of copper wiring
http://www.discussionpoint.org/forum/member.php?action=profile&uid=12328
How do I keep Copper from turning green?
http://heroicfantasygames.free.fr/Forum/viewtopic.php?p=211957#211957
History of Ancient Copper Smelting Pollution During Roman and Medieval Times Recorded in Greenland Ice
http://forumpark.munfoorumi.com/viewtopic.php?f=2&t=86
Fueling the future with copper
http://love666.me/viewthread.php?tid=697688&page=1&authorid=857084
Does the Conductivity of Copper Vary With Temperature?
http://rpg.six168.com/viewthread.php?tid=123715&extra=
Profiling the five largest copper mining companies in the world
http://the-hideout.site/Forum/showthread.php?tid=470