Here’s a fun video showing the rainbow of colors that anodized titanium can become. There are blues and purples and gold and it all changes so fast. It’s basically magic (or science!) that just applying voltage to a piece of titanium in an electrolytic bath can transform the color completely.
The lustrous patina that protects the backside of Apple's new iPad Mini isn't just some cheap shellac or sealant coat—it's actually "grown" on the metal itself in an electrochemical process known as anodization. Here's how.