Colour plays a large role in design esthetics. There are many ways to add colour into Jewellery work, applying patinas are one of the simplest methods; requiring very little equipment or in some kinds expense. Copper takes a patina especially well. Every metal has its own personality; I like to think of Copper as an Old, Smelly, Dirty, Drunk, Homeless Man; if you've worked with it, you understand why. Because Copper is such a dirty Metal it likes to oxidize; in simple terms: put it next to a chemical and it will react by changing colours.