Non-ferrous heavy metals is a collective term covering copper and copper-based non-ferrous metals (brass, bronze, nickel silver). Other nonferrous metals like zinc and tin are, for historical reasons, counted amongst the group of white metals.

The most important metal in this group is copper. This soft, reddish metal can be shaped easily and, given its good conductivity, it is essential for electronics and in electrical engineering. As a conducting material, it is used in cables, generators and transformers. Strip conductors in copper make it possible to further miniaturise and improve the performance of chips.

http://en.wikipedia.org/wiki/Copper
http://en.wikipedia.org/wiki/Brass
http://en.wikipedia.org/wiki/Bronze
http://en.wikipedia.org/wiki/Nickel_Silver