I have recently came across jewellery designers who use anodised aluminium. The colours achieved are incredible. They are vibrant and maintain a quality that I feel enamel finds hard to achieve.
I had a quick look into how these colours are achieved and found process information from John Moore (below).
"Anodising aluminium is the process of forming an absorptive layer of hard transparent oxide on the surface of the metal which can then accept dye. This is achieved by passing an electric current through the metal in a solution of sulphuric acid.
For practical reasons I do not anodise the metal myself and I buy pre-anodised sheet from a company that produce the material for industry.
The process begins at home in my basement where sheets of pre-anodised aluminium are cut into smaller pieces (approximately A5 size) and then submerged in baths of special aluminium dye, which is heated to between 40 and 60 degrees celsius. Using only four colours of dye I am able to achieve infinite colour ways by dipping into one dye after another any number of times, thoroughly rinsing the metal in between. Effectively I am building up layers of transparent colour but without contaminating each dye. I am currently using a 'dip dye' technique to achieve a subtle fade evenly across the metal, which is difficult and often unsuccessful resulting in a lot of waste material. Afterwards the metal is steamed for half an hour to seal the the pours in the oxide and fix the colour permanently." - taken from www.johnmoorejewellery.com
John Moore www.johnmoorejewellery.com
Helen Swan www.hswanjewellery.co.uk
Sophie Honeybelle www.honeybelle.co.uk
I think these are all stunning. I would definitely like to try experimenting with this material in the future!