Copper is a recyclable material 
http://bbs.astrology.org.tw/home.php?mod=space&amp;uid=120402 
 
Copper in the USA: Bright Future - Glorious Past 
http://heroicfantasygames.free.fr/Forum/viewtopic.php?p=211957#211957 
 
 
Manufacturing Process of Copper 
http://www.jangwontech.net/en/bbs/board.php?bo_table=en_qna&amp;wr_id=353958 
 
Abandoning fossil fuels bumps into high demand for copper 
http://n1sa.com/forum.php?mod=viewthread&amp;tid=7383821&amp;page=1&amp;authorid=167661 
 
History of Ancient Copper Smelting Pollution During Roman and Medieval Times Recorded in Greenland Ice 
http://wfmetin.com/bbs/viewthread.php?tid=95971&amp;pid=96650&amp;page=1&amp;extra=page%3D1#pid96650 
 
Copper manufacturing process 
http://homeopathyonlinemd.com/electro-homeopathic-forum/topic/does-the-conductivity-of-copper-vary-with-temperature/#postid-615141